Jaṭila sutta: Matted Hair Ascetics

So I have heard. At one time the Buddha was staying near Gayā on Gayā Head. Now at that time—during the cold spell when the snow falls in the January winter—many matted hair ascetics plunged in and out of the Gayā river. Plunging and showering, they served the sacred flame, thinking: “Through this there is purity.”

The Buddha saw them plunging in and out.

Then, understanding this matter, on that occasion the Buddha expressed this heartfelt sentiment:

“Purity doesn’t come from water,
no matter how many people bathe there.
One who has truth and principle,
they are pure, they are brahmins.”