Paṭhamabrahmacariyasutta

Suttapiṭaka · Saṁyuttanikāya · Mahāvaggasaṁyutta · Vol. 19 · Section 112

[112] And what, bhikkhus, is the holy life (brahmacariya)? It is just this Noble Eightfold Path (ariyo aṭṭhaṅgiko maggo); that is: right view … right concentration (samādhi). This, bhikkhus, is called the holy life.

English translation from the Pali (Siam Raṭṭha edition) — under review, not for citation.

This passage also appears in 1 other place

Vol. 19 · Section 100 — Paṭhamasāmaññasutta