Cetokhilasutta 9.3

9.3

Yo so, bhikkhave, bhikkhu satthari na kaṅkhati na vicikicchati adhimuccati sampasīdati, tassa cittaṃ namati ātappāya anuyogāya sātaccāya padhānāya.

This being so, their mind inclines toward keenness, commitment, persistence, and striving.