Sayyiduna Abu Hurayrah (may Allah be pleased with him) narrates: The Prophet (peace and blessings be upon him) met Sayyiduna Hudhayfah (may Allah be pleased with him) and intended to shake hands with him, but Sayyiduna Hudhayfah (may Allah be pleased with him) drew back and submitted: "I am in a state of major ritual impurity (janabah)." The Prophet (peace and blessings be upon him) said: "When a Muslim shakes hands with his brother, the sins of both of them fall away just as the leaves of a tree fall."
Al-Bazzar recorded it. Its chain contains a narrator, Mus'ab bin Thabit, whom Ibn Hibban declared thiqah (trustworthy), while the majority declared him da'if (weak).
Hadith Referenceمجمع الزوائد ومنبع الفوائد / كتاب الأدب / 12768