This episode is a narration of the 36th Sutta of the Middle Discourses of the Buddha, The Mahasaccaka Sutta, which translates as “the Longer Discourse with Saccaka”. In this discourse the Buddha and Saccaka discuss the difference between physical and mental development. The Buddha gives a long account of the various practices he did before awakening, detailing the astonishing lengths he took to mortify the body.

This translation of the Mahasaccaka Sutta is by Bhikkhu Sujato and was sourced from Sutta Central.

If you'd like to understand more about this sutta you could listen to a sutta study class led by Ajahn Brahm about this sutta.

May you all benefit from hearing the original teachings of the Buddha.