It is narrated from Muhammad bin Amr bin Hazm that the Messenger of Allah, peace and blessings be upon him, said: "If someone sneezes, respond to him (that is, when he says 'Alhamdulillah', say 'Yarhamuk Allah'), then if he sneezes again, respond to him, then if he sneezes again, respond to him, then if he sneezes again, say: 'You have caught a cold.'" Abdullah bin Abi Bakr said: I do not know whether the Messenger of Allah, peace and blessings be upon him, said this after the third time or after the fourth.