The word(s) "penitent" appears 3 time(s) in 3 verse(s) in Quran in Muhammad Habib Shakir translation.

(1) And when Musa said to his people: O my people! you have surely been unjust to yourselves by taking the calf (for a god), therefore turn to your Creator (penitently), so kill your people, that is best for you with your Creator: so He turned to you (mercifully), for surely He is the Oft-returning (to mercy), the Merciful.

(2) Who fears the Beneficent Allah in secret and comes with a penitent heart:

(3) Maybe, his Lord, if he divorce you, will give him in your place wives better than you, submissive, faithful, obedient, penitent, adorers, fasters, widows and virgins.