What is a true Friendship according to Shri Krishna? How can someone identify his true friends?
A true friend is a person who inspires us in the path of God, shields us from all vices and temptations, intercedes on our behalf with God, and prays for our spiritual welfare. Krishna is advising us inShrimad Bhagavt Gita 6.5 that one's own Atma is one's true friend.
आत्मैव ह्यात्मनो बन्धुरात्मैव रिपुरात्मनः।।6.5।।
English Translation By Swami Gambirananda -
6.5 One should save oneself by oneself; one should not lower oneself. For oneself is verily one's own friend; oneself is verily one's own enemy.
English Translation Of Sri Shankaracharya's Sanskrit Commentary By Swami Gambirananda -:
Certainly there is no other friend who can bring about liberation from this world. In fact, even a friend is an obstacle to Liberation, he being the source of such bondage as love etc. Therefore the emphatic statement, 'For one is one's own friend, is justifiable. Atma eva, oneself verily; is atmanah, It has been said that 'oneself is verily one's own friend, Because a physical friend can also be an obstacle in ones spiritual journey by becoming attached to him.
So according to Shri Krishna in Gita, our Atman is our true friend, whom we can trust since its the one who will lead us in our spiritual progress (Moksha) as well as will be responsible for our downfall.
According to Krishna, Krishna himself is to be trusted as the true friend. In this chapter of the Srimad Bhagavatam, Uddhava asks Krishna a series of questions:
My dear Lord Kṛṣṇa, O chastiser of the enemies, please tell me how many types of disciplinary regulations and regular daily duties there are. Also, my Lord, tell me what is mental equilibrium, what is self-control, and what is the actual meaning of tolerance and steadfastness. What are charity, austerity and heroism, and how are reality and truth to be described? What is renunciation, and what is wealth? What is desirable, what is sacrifice, and what is religious remuneration? My dear Keśava, O most fortunate one, how am I to understand the strength, opulence, and profit of a particular person? What is the best education, what is actual humility, and what is real beauty? What are happiness and unhappiness? Who is learned, and who is a fool? What are the true and the false paths in life, and what are heaven and hell? Who is indeed a true friend, and what is one’s real home? Who is a rich man, and who is a poor man? Who is wretched, and who is an actual controller? O Lord of the devotees, kindly explain these matters to me, along with their opposites.
And here are Krishna's answers:
Nonviolence, truthfulness, not coveting or stealing the property of others, detachment, humility, freedom from possessiveness, trust in the principles of religion, celibacy, silence, steadiness, forgiveness, and fearlessness are the twelve primary disciplinary principles. Internal cleanliness, external cleanliness, chanting the holy names of the Lord, austerity, sacrifice, faith, hospitality, worship of Me, visiting holy places, acting and desiring only for the supreme interest, satisfaction, and service to the spiritual master are the twelve elements of regular prescribed duties. These twenty-four elements bestow all desired benedictions upon those persons who devotedly cultivate them. Absorbing the intelligence in Me constitutes mental equilibrium, and complete discipline of the senses is self-control. Tolerance means patiently enduring unhappiness, and steadfastness occurs when one conquers the tongue and genitals. The greatest charity is to give up all aggression toward others, and renunciation of lust is understood to be real austerity. Real heroism is to conquer one’s natural tendency to enjoy material life, and reality is seeing the Supreme Personality of Godhead everywhere. Truthfulness means to speak the truth in a pleasing way, as declared by great sages. Cleanliness is detachment in fruitive activities, whereas renunciation is the sannyāsa order of life. The true desirable wealth for human beings is religiousness, and I, the Supreme Personality of Godhead, am a sacrifice. Religious remuneration is devotion to the ācārya with the purpose of acquiring spiritual instruction, and the greatest strength is the prāṇāyāma system of breath control. Actual opulence is My own nature as the Personality of Godhead, through which I exhibit the six unlimited opulence. The supreme gain in life is devotional service to Me, and actual education is nullifying the false perception of duality within the soul. Real modesty is to be disgusted with improper activities, and beauty is to possess good qualities such as detachment. Real happiness is to transcend material happiness and unhappiness, and real misery is to be implicated in searching for sexual pleasure. A wise man is one who knows the process of freedom from bondage, and a fool is one who identifies with his material body and mind. The real path in life is that which leads to Me, and the wrong path is sense gratification, by which consciousness is bewildered. Actual heaven is the predominance of the mode of goodness, whereas hell is the predominance of ignorance. I am everyone’s true friend, acting as the spiritual master of the entire universe, and one’s home is the human body. My dear friend Uddhava, one who is enriched with good qualities is actually said to be rich, and one who is unsatisfied in life is actually poor. A wretched person is one who cannot control his senses, whereas one who is not attached to sense gratification is a real controller. One who attaches himself to sense gratification is the opposite, a slave. Thus, Uddhava, I have elucidated all of the matters about which you inquired. There is no need for a more elaborate description of these good and bad qualities since to constantly see good and bad is itself a bad quality. The best quality is to transcend material good and evil.
But if you want to know the qualities of a true friend among ordinary humans, Krishna doesn't speak of it, though he does speak about trusting friends in this chapter of the Shanti Parva of the Mahabharata:
Neither an illiterate and foolish friend, nor a learned friend of fickle soul, deserves, O Narada, to know one's secret counsels.
But others in Hindu scripture do speak of the qualities of a true friend. Here is what the sage Sanatsujata says in this chapter of the Udyoga Parva of the Mahabharata:
Friendship is said to possess six indications; firstly, friends delight in the prosperity of friends, and secondly, are distressed at their adversity. If anyone asketh for anything which is dear to his heart, but which should not be asked for, a true friend surely giveth away even that. Fourthly, a true friend who is of a righteous disposition, when asked, can give away his very prosperity, his beloved sons, and even his own wife. Fifthly, a friend should not dwell in the house of a friend, on whom he may have bestowed everything, but should enjoy what he earneth himself. Sixthly, a friend stoppeth not to sacrifice his own good (for his friend).
Also, this chapter of the Devi Bhagavatam says that the true friend is the one who imparts devotion to Vishnu:
He is the true friend, indeed, the giver of one’s desired fruits, who imparts devotion to Hari.