If a Person is Exposed, It’s not his First Sin

Anas b. Mālik reports:

A young man who had stolen was brought to ʿUmar (for punishment). He said, “By Allāh I have never stolen before this time.” So ʿUmar responded, “You lie, Allāh would not (or does not) surrender a servant of His on the first sin.”

Abū Dāwūd, Al-Zuhd article 56, and others. Graded ṣaḥīh by Ibn Kathīr and others.