It is narrated from Sayyiduna Ammar bin Yasir (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) used to say regarding tayammum: "Striking the earth once with the hands is sufficient for the face and hands." Imam Darimi (may Allah have mercy on him) said: Its chain of narration is authentic. That is, strike the earth once with the hands and wipe the face and hands.