Sahih Adab al-Mufrad

It is narrated from Sayyiduna Ibn Abbas (may Allah be pleased with them both) that the Messenger of Allah (peace and blessings be upon him) went to visit a Bedouin who was ill (it is said that the Prophet’s practice was that when he went to visit a sick person) he would say: «لا بأس عليك ، طهور إن شاء الله» “No harm, if Allah wills, it will be a purification from sins.” (Sayyiduna Ibn Abbas, may Allah be pleased with them both, said:) That Bedouin said (Is it a purification? Never!) Rather, this fever is raging against an old man so that it may take him to the graveyard. The Prophet (peace and blessings be upon him) said: “Alright, then let it be as you say.”