The Tipiṭaka in Three Languages

Vibhaṅgasutta

Suttapiṭaka · Saṁyuttanikāya · Mahāvaggasaṁyutta · Vol. 19 · Section 936

[936] And what, bhikkhus, is the equanimity faculty (upekkhindriyaṃ)? Whatever feeling (vedanā) there is, bhikkhus, whether bodily or mental, that is neither comfortable nor uncomfortable — this, bhikkhus, is called the equanimity faculty.

English translation from the Pali (Siam Raṭṭha edition) — under review, not for citation.

This passage also appears in 5 other places