The word(s) "unbelief" appears 1 time(s) in 1 verse(s) in Quran in Saheeh International translation.

(1) Muhammad is not but a messenger. [Other] messengers have passed on before him. So if he was to die or be killed, would you turn back on your heels [to unbelief]? And he who turns back on his heels will never harm Allah at all; but Allah will reward the grateful.

(سورة آل عمران, Aal-i-Imraan, Chapter #3, Verse #144)
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