The hadith of Abu Juhayfah and Qays bin Abbad from Sayyiduna Ali bin Abi Talib (may Allah be pleased with him) has already passed, concerning what he had (narrated) from the Prophet (peace and blessings be upon him), (written) in the scroll: "A Muslim is not to be killed in return for a disbeliever."
And in this there is an indication of the weakness of the (narration) that follows.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الجنايات / Q15934