It is narrated from Sayyiduna Ka'b bin 'Ujrah, may Allah be pleased with him, that he was with the Messenger of Allah, peace and blessings be upon him, (during Hajj) and lice were troubling him (Ka'b, may Allah be pleased with him) on his head. Then the Messenger of Allah, peace and blessings be upon him, ordered him to shave his head and said: "Fast for three days, or feed six needy people—each person two mudd—or offer the sacrifice of a goat. Whichever of these you do will suffice for you."