Is prayer and peace upon Muhammad the cause of every blessing in religion and in this world, and does it ward off every disliked thing in them both?

This statement is reprehensible exaggeration, as the Prophet (peace be upon him) forbade exalting him, saying: "Do not exaggerate in praising me as the Christians exaggerated in praising Jesus, son of Mary. Indeed, I am only a slave, so say: 'Allah's slave and His Messenger.'"

His (peace be upon him) mission is one of the greatest blessings upon the Ummah. Through him, Allah guided us to goodness and clarified the path to Paradise, as Allah Almighty says: "Certainly did Allah confer [great] favor upon the believers when He sent among them a messenger from themselves, reciting to them His verses" (Aal 'Imran: 164).

As for describing him (peace be upon him) as the cause of every religious and worldly blessing and the repeller of every harm, this is reprehensible exaggeration, because all blessings are from Allah Almighty, as He says: "And whatever favor you have - it is from Allah" (An-Nahl: 53). And the repeller of harm is Allah alone, as He says: "And if Allah should touch you with adversity, there is no remover of it except Him" (Al-An'am: 17).

So, all blessings are from Allah, and among the greatest of them is the mission of the Prophet (peace be upon him).