Majma al-Zawaid — Hadith 1412

Sayyiduna al-Asla' bin Ka'b (may Allah be pleased with him), who belonged to Banu al-A'raj, narrates: I used to serve the Prophet (peace and blessings be upon him). He said to me: "O Asla', get up and show me how such-and-such is." I said: "O Messenger of Allah, I have become sexually impure (junub)." The Prophet (peace and blessings be upon him) remained silent for a while, and then Sayyiduna Jibril (peace be upon him) came down to him with the command to perform dry ablution (tayammum) with clean earth. He said: "O Asla', get up and perform dry ablution." The narrator said: Then Sayyiduna al-Asla' (may Allah be pleased with him) demonstrated to me how the Prophet (peace and blessings be upon him) had taught him dry ablution. He said: The Prophet (peace and blessings be upon him) struck the ground with his palms, then rubbed one against the other, then shook them off, and then with them wiped the outer and inner sides of his forearms.
Al-Tabarani recorded it in al-Mu'jam al-Kabir; its chain contains al-Rabi' bin Badr, and the hadith scholars are agreed on his being da'if (weak).