Khalid bin Ma'dan narrates from Mu'adh (may Allah be pleased with him), who said: The Messenger of Allah (peace and blessings of Allah be upon him) said: "Whoever reproaches his (Muslim) brother for a (past) sin, then this person will commit that (sin) before he dies." This refers to the sin from which he has already repented. (Tirmidhi) And he said: This hadith is gharib, its chain is not connected because Khalid did not meet Mu'adh bin Jabal (may Allah be pleased with him). Its chain is weak. Narrated by al-Tirmidhi.