Kulasutta

Suttapiṭaka · Saṁyuttanikāya · Nidānavaggasaṁyutta · Vol. 16 · Section 665

[665] He was dwelling at Sāvatthī ... There the Blessed One ... "Bhikkhus, just as any families that have many women and few men are easily assailed by robbers, by pot-thief burglars (kumbhatthenaka), so too, bhikkhus, any bhikkhu in whom the liberation of mind (cetovimutti) by loving-kindness (mettā) is undeveloped and uncultivated is easily assailed by non-human beings."

English translation from the Pali (Siam Raṭṭha edition) — under review, not for citation.