Hinduism is known for its wide acceptance of other cultures. Most religions, like Christianity, Islam, etc. have very strict rules regarding this. They are not allowed to worship or visit any other religious places. But in Hinduism, I don't see such restrictions like in other religions- Hindus are allowed to visit other religious and pray to Jesus, Allah, and Buddha if they want. Why is it so?
Edit: As MKaama mentioned, there could be different opinions among different philosophical groups within Hinduism regarding this, but I am asking based on a general view, specifically compared to other religions like Christianity, Islam or Buddhism where visiting other religious places have very strict restrictions.
Because Hinduism is not structured like Islam or Christianity. There is no 'one' supreme god or 'one' single book to guide you. Everyone is free to find their own way to the ultimate freedom (moksha) and most of the religious books (Vedas, Upanishads, Geeta etc.) prohibit harming other living things. As long as you don't hurt anyone, you can live even without praying and not be condemned. If however you wish to pursue spiritual path to achieve moksha, you are free to worship any god/force/inspiration in a harmless way.
I am an atheist and have learnt a little about a few religions. I have come to believe that Hinduism is the next best thing to atheism and agnosticism.
I had answered this question 6 years ago, when I was way more ignorant (than now :) ), and largely unaware of my ignorance, and had many presumptions, and misconceptions. (Reading this extremely narcissistic, and idiotic line makes me cringe every time: "I am an atheist and have learnt a little about a few religions".. )
Now (year 2020), I would't even dare to attempt answering this question, as I wouldn't know what you mean by Hinduism, atheism, agnosticism etc. , let alone compare it to other religions (which I know even less about), because these concepts are defined / understood differently by almost everyone. Specially defining hinduism is even more difficult cause there isn't one definition / practice / book / institution accepted by ALL.
Also, though generally Hindu population (or a large section of it, if not the religion itself) do not have restriction on visiting other religious places, there are few Hindu temples, which do not allow non-hundu people to enter. So its not as open a culture / religion EVERYWHERE in India as well.
I did not want to delete / edit original text in my answer because it is an accepted answer, and has been upvoted a few times, so changing it would feel like cheating, even if the answer turns out to be inaccurate, (or
as some comments below argue, completely wrong).
My original answer, would probably, still have some relevance, if you consider the question only asks why "Hindus" (not hinduism) have no restrictions, and the fact that most Hindus (even some religiously sincere ones), haven't read, are aware of, or even considered the question of what should be, THE authoritative book / god / person / practice etc. to follow.
Hinduism is a way of living, it is a culture passed down by ancient rishis and Yogis. It just helps to realize who you are. As a culture, it does not need any conversions based on religions. Even if there are so many beliefs, rituals and sacraments in Hinduism it all leads to the single road, self-realization. According to Hinduism, for attaining self-realization you can follow any path. So for being a Hindu you do not need any conversions.
This culture knows that every God is the same. They see God in everything, in trees, in animals, in stones and in every human. So according to Hindus, Krishna, Jesus, Allah and Shiva are all equal.
The most important texts in Hinduism, the 4 Vedas, mahavakyas (ultimate messages) are the following.
Rig Veda - prajñānam brahma - Wisdom/consciousness is Brahman (highest truth)
Atharva Veda - ayam ātmā brahma - I am this Self is Brahman
Sama Veda - tat tvam asi - You are that(Brahman)
Yajur Veda - aham brahmāsmi - I am that (Brahman)
Hindus do not pray "Hindu Samastha Sukhino Bhavanthu", instead they pray "Loka Samastha Sukhino Bhavanthu" (May all world be well). That world includes people of every religion, atheist and every living being.
The answer to this question is to be found in Swami Tapasyananda's insightful explanation of Gita 4.11 which says
O Partha! Whosoever worships Me through whatsoever path, I verily
accept and bless them in that way. Men everywhere follow My path.
Swami Tapasyananda in his Commentary on the Gita says the following on this verse:
'This verse is the fundamental tenet of the universal religion.
Wherever worship is done, only the one Supreme Being is worshipped.
No one, except the perfected sage, can worship Him in His fullness,
since the human mind can grasp only limited aspects of Him. The more
an individual or a community is evolved, the more noble and
comprehensive will be their conception of the Deity. But the less
evolved man too is adoring the same Deity, grasping such aspects of
His as his undeveloped mind would allow. It is just like various forms
being chipped from a huge block of marble. The more skilled the
workman, the more artistic will be the forms chipped out of the block.
Even if it is crude, it is of the same block. Such are the various
conceptions of the Deity; none can claim that his conception embraces
the whole of Him, because He cannot be contained within the limitation
of a mind, as a bottle cannot contain the whole of the sea. He reveals
only what one is fit to receive. So according to the stages of human
evolution, there will be different conceptions of the Deity, and the
followers of one, even if they think theirs is more refined, need not
look down upon others as heathens or Kaffirs worshipping false
Deities, and consider themselves alone as the followers of the true
Deity. For whatever the path, God approaches man through that path,
and if the faith of the votary is genuine, he will be led to higher
and higher forms of worship. So the followers of every religion must
have respect for, and have acceptance of, the faith and form of
worship of other religions in spite of the differences that are sure
to prevail in their ideologies and practices. For it is the same God
that is worshipped by them all. Just as all rivers, in spite of their
divergent courses, lead to the same ocean, so do all faiths lead to
Him, i.e., take one to the same God who inspires them all. This Gita
teaching has been proclaimed to the modern world by Sri Ramakrishna in
his saying: "As many faiths, so many paths".'
Srimad Bhagavad Gita translated by Swami Tapasyananda
The above interpretation of Gita 4.11 does not mean that Hindus regard all religions to be same or of equal value as can be seen from the following quote:
You must remember that humanity travels not from error to truth, but
from truth to truth; it may be, if you like it better, from lower
truth to higher truth, but never from error to truth. Suppose you
start from here and travel towards the sun in a straight line. From
here the sun looks only small in size. Suppose you go forwards a
million miles, the sun will be much bigger. At every stage the sun
will become bigger and bigger. Suppose twenty thousand photographs had
been taken of the same sun, from different standpoints; these twenty
thousand photographs will certainly differ from one another. But can
you deny that each is a photograph of the same sun? So all forms of
religion, high or low, are just different stages towards that eternal
state of light, which is God Himself. Some embody a lower view, some a
higher, and that is all the difference.
Complete Works of Swami Vivekananda, IV, p147
Why are Abrahamic faiths so strict about visiting places of other religions? The answer is that monotheism of Abrahamic faiths is really my-theism. It is either my way or the highway.
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