In Christianity, one has the holy Bible and in Islam one has the holy Quran. Which scriptures should a Hindu always follow? Which scripture can a Hindu look up for references?
Hindu scripture is made up of two categories, Shruti and Smriti. Shruti means "that which is heard" (what Christians would call "revelation"). Hindus believe that from time immemorial, sages known as Dhrishtas (literally "seers") have, during a state of Tapasya (deep meditation), heard sacred verses directly from the gods. As I discuss in this question, the Dwapara Yuga (the age before the one we're currently living in), these verses were compiled by a sage named Krishna Dwaipayana Veda Vyasa (or Vyasa for short) into a set of four books we call the Vedas. (Technically Vyasa only compiled the first three books - Rig, Yajur, and Sama - while the Atharvana Veda is attributed to the sages Angiras and Atharvan.) As the words of the Vedas are believed to be divine in origin, they are held to be the foremost authority of the Hindu religion. As Rama says in the Ayodhya Kanda of the Ramayana, the Vedas "have the foundation in Truth [and] one should thoroughly surrender to truth."
[EDIT: I should add that each of the four Vedas is divided into four portions: Samhitas, which consist of hymns to various gods; Brahmanas, which provide instructions on the proper conducting of important rituals; Aranyakas, which provide a guide to rituals meant for forest-dwellers and hermits; and Upanishads, which consist of conversations between teachers and students which clarify the philosophical message of the Vedas.]
The second category of Hindu scripture is called Smriti, literally "that which is remembered". It refers to those sacred texts of Hinduism which were composed by human authors and then passed down by teacher to student via oral tradition. Note that just because the specific words of these scriptures were composed by humans, that does not mean that they're not divinely inspired. (It's similar to how in the Bible, the words "I am the Lord thy God who delivered thee from Egypt" are thought to be words that God himself chose, whereas the Torah as a whole is believed to be authored by Moses but inspired by God.) There are numerous works that are called Smriti, but among the most prominent works are the Ramayana, the Mahabharata, and the Puranas.
The Ramayana is an epic poem compiled by sage Valmiki, and it deals with the life of Rama, an incarnation (AKA avataram) of the god Vishnu, who fought the demon Ravana to rescue his wife Sita. The Mahabharata is also an epic poem, one of the longest in the world. It was composed by Vyasa (the same guy who compiled the Vedas), and it discusses a great war between two factions of the same family, the Pandavas and the Kauravas. Prominently featured in the Mahabharata is the Pandavas' cousin Krishna, another incarnation of Vishnu. In the beginning of the war, one of the Pandavas, Arjuna, is reluctant, confused about what the righteous path is, so Krishna gives him a discourse known as the Bhagavad Gita, a guide to how to righteously live one's life. While the Mahabharata as a whole is considered to be of lesser authority than the Vedas, since the words are humanly composed, the Bhagavad Gita is often considered to be a fifth Veda, because it is the words of Krishna and is thus of divine origin.
Finally there are the Puranas, composed by (you guessed it) Vyasa, a collection of 18 major works and hundreds of ancillary works relating the creation of the Universe, the history of Man through the ages, and the stories of the three major gods of Hinduism: Brahma, Vishnu, and Shiva.
The most common that all sects of Hinduism can agree on would be the Bhagavad Gita.
It is commonly accepted to be one of the oldest scriptures in the world, and it concisely describes the philosophy of soul, God, and their relationship.
In Hinduism, every individual has unconditional freedom. Every person in this culture can live in any manner one finds right. Hence, there are no prescribed scriptures that every Hindu has to necessarily follow.
However there are thousands of scriptures in Hinduism from which a person can pick and choose anything. The purpose of these scriptures is to help the individual in one's spiritual evolution and not to serve as a rule book that should be thrust upon one.
The oldest known scriptures in Hinduism are the Vedas. The Vedas are the cumulative work of sages in ancient India as a result of their deep penance. They were passed on in the form of oral recitals (śruti). Vedas provide information on broadly two major aspects - Philosophy (Highest Knowledge) and rituals. The philosophy aspect of Veda is also referred to as the Upanishads.
The Mahavakyas are essential phrases (mantras) of the Upanishads. It serves as a quick summary of the Vedas. It consists of 4 phrases (vakya). Each of the sayings conveys the nature of God (Brahman). The Mahavakyas convey everything that Hinduism tries to convey regarding God.
Every individual is unique. Every individual comes from a varying plane of understanding of God. Each individual's understanding is dependent on multiple factors such as their experiences in life, upbringing, social environment, intellectual capacity, etc. In order to help the most people, Hindus in the past created different scriptures to help each individual. It helps the individual to experience the Mahavakyas by oneself. So for the purpose of covering a wide variety of people, a wide variety of scriptures were also created in the hope that each individual attains self-realization (Nirvana).
There are thousands of such scriptures in Hinduism for this purpose. They include the Mahabharata and Ramayana. The Gita is a part of the Mahabharata which deals with the philosophical aspect of the Mahabharata. (Like the Upanishads are to the Vedas).
There are many more scriptures in Hinduism that were created for specific purposes to meet the varying demands of people and social conditions. This includes the Manusmriti .
The exhaustive list of prominent scriptures are available at Wikipedia.
As you might have observed Hinduism has no defined sets of rules, principles, scriptures, rituals, divisions, etc. Yet everything is practiced by many of the Hindus. The reason for this variety within Hinduism is a result of the freedom which the culture bestowed upon the people. Hence one might find ample instances/phrases from different scriptures that seem to contradict each other, etc. But, please keep in mind that each phrase is highly contextual. So one size (phrase) does not fit all (contexts). Moreover, there is absolutely no confirmation on the authenticity of the scriptures mentioned above. It is possible that some of the scriptures have been tampered with (eg. Manusmriti).
Inspite of all these short-comings, Hinduism continued to exist because each individual used his/her discrimination in finding, listening/reading, understanding, interpreting, and applying the scriptures.
Apart from scriptures, Hinduism also encourages one to seek answers oneself through meditation. So even if every single scripture is lost/manipulated, a Hindu can always retrace the path and find answers oneself.
Every scripture in Hinduism is a tool to help find the larger goal of self-realization.
We have four Vedas each of which in turn has samhitas, Brahmanas, Aranyakas and Upanisads. This is generally considered as Sruti. Then we have other texts like Dharma Sastras, Puranas and Itihasas. These are generally considered as Smrti. However very minute percent of the original Vedas is available now and most of those who get lost in Vedas are interested in fruitive gains like elevation to higher material planets for better sense enjoyment. However Lord Krishna says in the Gita that the purpose of Vedas is to know Him only and asks Arjuna to rise above the Vedas.
BG 2.42-43: Men of small knowledge are very much attached to the flowery words of the Vedas, which recommend various fruitive activities for elevation to heavenly planets, resultant good birth, power, and so forth. Being desirous of sense gratification and opulent life, they say that there is nothing more than this.
BG 2.45: The Vedas deal mainly with the subject of the three modes of material nature. O Arjuna, become transcendental to these three modes. Be free from all dualities and from all anxieties for gain and safety, and be established in the self.
BG 2.53: When your mind is no longer disturbed by the flowery language of the Vedas, and when it remains fixed in the trance of self-realization, then you will have attained the divine consciousness.
BG 15.15: I am seated in everyone's heart, and from Me come remembrance, knowledge and forgetfulness. By all the Vedas, I am to be known. Indeed, I am the compiler of Vedānta, and I am the knower of the Vedas.
However Bhagavad Gita is considered to be the essence of all Upanishads (which are part of Vedas) and it can give us the true knowledge of the Vedas.
partho vatsah su-dhir bhokta
dugdham gitamrtam mahat
“This Gitopanisad, Bhagavad-gita, the essence of all the Upanisads, is just like a cow, and Lord Krsna, who is famous as a cowherd boy, is milking this cow. Arjuna is just like a calf, and learned scholars and pure devotees are to drink the nectarean milk of Bhagavad-gita.” (Gita-mahatmya 6)
Therefore Gita is one such scripture that is very well suitable for the people of modern age and is accepted by all schools of transcendentalists (personal and impersonal)
While the Gita is the hidden treasure in Mahabharata, Vyasadeva was not satisfied even after giving the Vedas and the Mahabharata. This we see in Srimad Bhagavatam:
SB 1.4.28-29: I have, under strict disciplinary vows, unpretentiously worshiped the Vedas, the spiritual master and the altar of sacrifice. I have also abided by the rulings and have shown the import of disciplic succession through the explanation of the Mahābhārata, by which even women, śūdras and others [friends of the twice-born] can see the path of religion.
SB 1.4.30: I am feeling incomplete, though I myself am fully equipped with everything required by the Vedas.
At this point Narada, the guru of Vyasa, advises him to write Srimad Bhagavatam. This we see in chapter 5 where the events leading to Bhagavatam were given:
SB 1.5.12: Knowledge of self-realization, even though free from all material affinity, does not look well if devoid of a conception of the Infallible [God]. What, then, is the use of fruitive activities, which are naturally painful from the very beginning and transient by nature, if they are not utilized for the devotional service of the Lord?
SB 1.5.13: O Vyāsadeva, your vision is completely perfect. Your good fame is spotless. You are firm in vow and situated in truthfulness. And thus you can think of the pastimes of the Lord in trance for the liberation of the people in general from all material bondage.
Further Bhagavatam is clear about it's purpose right from the beginning as we see below:
SB 1.1.2 — Completely rejecting all religious activities which are materially motivated, this Bhagavata Purana propounds the highest truth, which is understandable by those devotees who are fully pure in heart. The highest truth is reality distinguished from illusion for the welfare of all. Such truth uproots the threefold miseries. This beautiful Bhagavatam, compiled by the great sage Vyasadeva [in his maturity], is sufficient in itself for God realization. What is the need of any other scripture? As soon as one attentively and submissively hears the message of Bhagavatam, by this culture of knowledge the Supreme Lord is established within his heart.
SB 1.1.3 — O expert and thoughtful men, relish Srimad-Bhagavatam, the mature fruit of the desire tree of Vedic literatures. It emanated from the lips of Sri Sukadeva Gosvami. Therefore this fruit has become even more tasteful, although its nectarean juice was already relishable for all, including liberated souls.
In the Gita, towards the end, Lord Krisha says:
sarva-dharman parityajya mam ekam saranam vraja - Abandon all varieties of religion and just surrender unto Me.
Similarly bhagavatam start with
dharmah projjhita-kaitavo ’tra Completely rejecting all religious activities which are materially motivated, this Bhagavata Purana propounds the highest truth. And it says further
srimad-bhagavate maha-muni-krte kim va parair This beautiful Bhagavatam, compiled by the great sage Vyasadeva [in his maturity], is sufficient in itself for God realization. What is the need of any other scripture?
Gita tell us to surrender to Krishna and Bhagavatam tells us about glories of His name, qualities and pastimes. Bhagavatam contains the practical examples of how to surrender to Krishna and execute devotional service. Also Lord Caitanya Mahaprabhu considered Bhagavatam as the natural commentary on Vedanta Sutra.
Therefore these two scriptures Bhagavad Gita (Instructions of Krishna) and Srimad Bhagavatam (Descriptions about Krishna) are the essence of all Vedic literarture and are most suitable to guide us to ultimate perfection.
What about doing whatever you want to do as suggested in Gita? Doesn't Hinduism tell us to do whatever we want to do?
Bg 18.63 — Thus I have explained to you knowledge still more conﬁdential. Deliberate on this fully, and then do what you wish to do.
Well, Lord Krishna doesn't stop with that. The government let's people do what ever they want but it also punishes those when the violate the law. Similarly laws of nature will give us reactions when we act whimsically. While Lord Krishna tells Arjuna to do whatever he wants he can do that is not what the Lord recommends him to do. As a kind father of all living entities the Lord pours out his heart in the next verses:
Bg 18.64 — Because you are My very dear friend, I am speaking to you My supreme instruction, the most conﬁdential knowledge of all. Hear this from Me, for it is for your beneﬁt.
Bg 18.65 — Always think of Me, become My devotee, worship Me and offer your homage unto Me. Thus you will come to Me without fail. I promise you this because you are My very dear friend.
Bg 18.66 — Abandon all varieties of religion and just surrender unto Me. I shall deliver you from all sinful reactions. Do not fear.
This last instruction is His most well-wishing, merciful and loving instruction for those who want to follow and as I said above Gita and Bhagavatam will help us follow this.
Hindu attitude towards scripture is different from the Abrahamic faiths. Hindus should read at least once the Vedas, the Itihasas and the Puranas. However, simply reading is not enough.
They study the Vedas and discuss. But they do not realize the Ultimate Reality just as a spoon does not know the taste of food.
The head carries the flowers, the nose knows the scent. The people study the Vedas. But, very few persons understand the same.
Not knowing the Reality of the self, a fool is infatuated by the sastras. When the goat stands in the shed, the shepherd seeks for it in the well in vain.
The knowledge of the sastras is not competent to destroy the infatuation accruing from worldly affairs. …. Having studied the Vedas and realized their essence the wise man should leave all the sastras just as one desiring corn leaves the husk.
Just as one satiated with nectar has no use of food, no one who is in search of Reality has anything to do with the sastras.
One cannot obtain release by reading the Vedas of the sastras. Release comes from experience, not otherwise, O son of Vinata.
[Garuda Purana, Dharma Khanda, Chapter XLIX]
Well, i find "a scripture every Hindu should abide by" difficult to answer. As it comes to individual's choice whether he delights in following Srimad Bhagvad Gita or Srimad Ramayana or any other scripture. Therefore, it is about his preference and certainly, he is not wrong in any of the cases.
As you(S Rahul Bose, questioner) yourself wrote:
Hence, there are no prescribed scriptures that every Hindu has to necessarily follow.
But still writing something for answer; the source of Hindu religion, as quoted by Swami Vivekananda at World Parliament of Religions (here- page 2), are the Vedas.
The Hindus have received their religion through revelation, the Vedas. They hold that the Vedas are without beginning and without end.
The problem with the above explanations is that they are only scratching the surface. If one needs scriptures to follow, I suggest Geeta.
Geeta has sole authority to determine all the scriptures' credibility. If one removes all the names and stories from it, they can see the hidden meaning in Geeta which is devoid of romance and is of pure knowledge.
It specifies the true nature of Prakriti and Purusha. And at the same time advocates Bhakthi Yoga, covers all schools of thought.
My take is, The composer of Geeta had foreseen the current state of our Dharma and took precautions by putting all the Jnana into one capsule. Time can do lot of tinkering with the truth. This resulted in our current state of affairs. But the truth is, Geeta is the ultimate knowledge which is given by our forefathers. Lets not get overwhelmed by size of our scriptures. I can elaborate this, if any one needs it.
There is no such need in the Hindu dharma. Let us start by talking about the Bible first which is history-centric:
"The word 'Bible' is indiscriminately used in the West to refer to the sacred scriptures of other traditions. However, as used in Jewish and Christian traditions, the term refers to a specific closed canon of history-centric texts which are regarded as the normative and authentic teachings of those religions. The core of the Jewish Bible is the Torah, which contains the five books of Moses (the Pentateuch) and a number of prophetic commentaries, songs, hymns, historical narratives and wisdom writings. For Christians, sacred scripture is the Hebrew Bible (called the Old Testament) and the New Testament, which consists of the four Gospels, Acts of the Apostles, letters written to communities or individuals or churches, and the Book of Revelation. For Muslims, the sacred scripture is the Qur'an, which is seen as the corrected and perfect form of Biblical revelation, with additional, new revelations woven into it that supersede the Jewish and Christian Bible.
In all cases, these scriptures have a special canonical status: they are authoritative, and also final in certain traditions. They were given at a defined point in history, usually when the religion began to spread beyond its original homeland, to establish a canon, “a textual base that would be authoritative and final. This process of forming a canon and declaring it closed happened in the Hebrew and Christian traditions in the first two centuries of the Common Era, during the period when Christianity was taking shape and the religion of Israel had to cope with the destruction of the temple and the dispersion of the people into exile.
The status of sacred scripture in these traditions differs remarkably from the status of written texts in Indian traditions. The Hebrew Bible is clearly a collection of texts written at widely different times and in different genres, but in most Christian formations it is treated theologically as if it had one single author and as if the events described literally happened. Even the famous Ten Commandments are given in the context of a specific moment in the history of Israel, a moment which is narrated at great length though interpreted variously in the three Abrahamic religions. History, in short, plays a significant role in the Hebrew Bible and in the New Testament.
Seen from a Vedic point of view, the Bible is, for the most part smriti (a written historical account) as opposed to shruti (direct enlightenment experience). The Bible entirely consists of third-party accounts, what X said to Y. A gospel is a written account of the history of Jesus' life, ministry, death, burial, and resurrection and not an account of Jesus' own first-person revelations or experiences. We might call the New Testament 'Jesus Smriti' to distinguish it from shruti.
Furthermore, the New Testament is not written in a sacred language but in a kind of popular Greek which was common throughout the Mediterranean in its time. For Christians, this language is secular, and its text merely 'points to' something else, but it does not embody, i.e., it is not literally the person of Jesus. While some fundamentalist Christians insist that the Bible is inerrant in every detail, and the more liberal Christians hold that only the historical events of the birth, death and resurrection of Jesus are absolutely true, both camps regard the events described as the 'word' of inner truth and not the vibrations per se.
In contrast, and as discussed above, Indian scriptures are divided into shruti and smriti, i.e., a set of wisdom writings that reflect direct inner embodied knowing of the divine and a disparate group of second-order commentaries and contextual applications. The contextual nature of Indian culture has interplay between that which is constant and that which changes, between the stable patterns of reality and momentary reality.52 Yet each is kept distinct. Shruti is inspired and timeless revelation, an eternal authorless knowledge similar to any physics formula. On the other hand, the contextual truths of smriti are ever-changing and cannot be frozen into canons. Under new circumstances, smritis – as human constructs – must be written again and again as befits time and place. Sri Aurobindo explains this requirement as follows:
First of all, there is undoubtedly a Truth one and eternal which we are seeking, from which all other truth derives, by the light of which all other truth finds its right place, explanation and relation to the scheme of knowledge … Secondly, this Truth, though it is one and eternal, expresses itself in Time and through the mind of man; therefore every Scripture must necessarily contain two elements, one temporary, perishable, belonging to the ideas of the period and country in which it was produced, the other eternal and imperishable and applicable in all ages and countries.
Although shruti (such as primordial sounds) is authorless, the reader/ listener provides the context in which it is interpreted. Smriti has two contexts: that of the author who constructs it and that of the reader who interprets it. The Judeo-Christian religions have collapsed shruti and smriti into one book and frozen it in time without the evolving context. Again, Catholicism seems to take a more sophisticated view here than does fundamentalist Protestantism. Protestants, who in principle wish to rid themselves of the control of the institutional church and its priesthood, do not recognize tradition as authoritative and normally adopt Luther's “motto: sola scriptura ('scripture alone' is authoritative). They have replaced an authoritarian church with an authoritarian book.
Since the Second Vatican General Council (1962–65), which laid down the template for the future of the Roman Catholic institutional church, Catholics have seen God's revelation as consisting of two strands, Bible and tradition, which some modern theologians would like to equate with shruti and smriti, respectively. But there are several reasons why the comparison can be taken only so far. For one thing, the Bible, unlike shruti, already includes a great deal of history. This makes the Bible smriti-dominated, which is consistent with the history-centric metaphysics of the Judeo-Christian traditions. Secondly, Christian tradition is specifically the experience of the Church, i.e., its history of interpretation and adaptation and not a set of records of the results of inner science.
The highly institutionalized structure of the Church means that its interpretations of scripture are controlled by a formal centralized authority. Dissent does exist, as in the present debates over homosexuality, women priests, stem cell research, etc., but it is usually initiated by groups marginalized or persecuted by the Church and takes effect slowly and after much resistance from authorities. Moreover, the various denominations of churches have become highly experienced at managing such threats over time. Challenging the core sacred text is deemed heresy or blasphemy. What would seem to be required are smritis that could be altered in response to the changing contexts of changing times. As it stands, any possibility of change rests with the same high priests and licensed ministers who maintain their power and control through institutional authority.
Since they emerged from multiple sources and are not institutionally regulated, smritis have enabled Hinduism to remain open to change without the need for violent wars or internal schisms. Westerners find it difficult to comprehend the Indian notion of sva-dharma ('my dharma', or personalized dharma), which is flexible, specific to a given space and time, and meant to be creatively discovered."
Above is an excerpt from the book Being Different by Rajiv Malhotra