Abdullah bin Ka'b narrates about his father (Sayyiduna Ka'b bin Malik, may Allah be pleased with him) that he said: O Messenger of Allah (peace and blessings be upon him)! What is your opinion regarding the medicines we use, or the incantations we recite, or other such actions—do they change the destiny decreed by Allah? The Prophet (peace and blessings be upon him) said: O Ka'b, rather, these are also a part of Allah's decree.
(Imam Ibn Hibban, may Allah have mercy on him, says:) The narrator named Amr bin Harith Hamsi is trustworthy; he is not Amr bin Harith Misri.