When Hazrat Hamzah (radhiyallahu ‘anhu) returned home, shaitaan began to instil doubts in his mind telling him, “O Hamzah! You are one of the leaders of the Quraish! How could you have followed this saabi (one who abandoned the religion of his forefathers)? Why have you abandoned the religion of your forefathers? It would have been better for you to die than to do this!”
Due to the attacks of shaitaan, Hazrat Hamzah (radhiyallahu ‘anhu) fell into some uncertainty and doubt. Hazrat Hamzah (radhiyallahu ‘anhu) relates, “I then turned to Allah Ta‘ala and made the following du‘aa:
اللهم إن كان رشدا فاجعل تصديقه في قلبي وإلا فاجعل لي مما وقعت فيه مخرجا
O Allah! If this religion that I have accepted is guidance, place its conviction into the depths of my heart! If it is not guidance then make a way for me to come out of it!”
According to another narration, Hazrat Hamzah (radhiyallahu ‘anhu) passed the night in this state of anxiety and restlessness. He was unable to sleep for even a moment. When this anxiety persisted and did not cease, he proceeded to the haram and made the following du‘aa with utmost humility, “O Allah! Open my heart to accept the truth and remove these doubts from my heart!”
Hazrat Hamzah (radhiyallahu ‘anhu) says, “I had barely completed making this du‘aa when all the reservations and doubts disappeared from my heart, leaving my heart filled with conviction and true faith. Immediately the next morning, I presented myself before Rasulullah (sallallahu ‘alaihi wasallam) and gave him an account of what had transpired. Rasulullah (sallallahu ‘alaihi wasallam) made du‘aa for me to remain steadfast and firm upon Islam.
(Seeratul Mustafa 1/182-183)