Of all the deep books of Eastern wisdom, the two that have most influenced me are the Tao Te Ching of Laotse and the Bhagavad Gita, a selection of some 700 lines from India’s national epic, The Mahabharata. Both are relatively short, yet abruptly different from the theistic traditions of the Judaeo-Christian and Islamic faiths.
I was first introduced to the Bhagavad Gita in 1975, on the bus between Chichen Itza and Mérida in Yucatán. I was sitting next to a cute Canadian girl who, as I recall, berated me for being too pompous. (She was right.) She gave me her copy of the Hindu scripture as a corrective to my sense of self-importance. Since then, I have read it several times.
Arjuna is with the god Krishna at the battlefield of Kurukshetra. As he scans the Kaurava army arrayed on the field against him, he expresses doubts about his role in fighting the battle. The Bhagavad Gita is the dialogue between Arjuna and Krishna on the subject:
Look upon pleasure and pain, victory and defeat, with an equal eye. Make ready for the combat, and thou shalt commit no sin.
He who wherever he goes is attached to no person and to no place by ties of flesh; who accepts good and evil alike, neither welcoming the one nor shrinking from the other—take him to be the one who is merged to the Infinite.
In the end, Arjuna resolves to commit himself to the battle. This is all very different from turning the other cheek, and certainly a good deal bloodier.
The quotes above are from the edition I read most recently, the translation for Shambala Pocket Classics by Shri Purohit Swami.