Sahih al-Bukhari · The Book of Asking Permission

21- بَابُ مَنْ لَمْ يُسَلِّمْ عَلَى مَنِ اقْتَرَفَ ذَنْبًا، وَلَمْ يَرُدَّ سَلاَمَهُ حَتَّى تَتَبَيَّنَ تَوْبَتُهُ، وَإِلَى مَتَى تَتَبَيَّنُ تَوْبَةُ الْعَاصِي:

(21) Chapter. He who does not greet a person who has committed a sin, and the one who does not reply to his greeting till the evidence of his repentance becomes obvious. And up to what time limit (one should wait for) till the repentance of a sinner is known.

1 hadith · references 6255–6255