Surah 36. Yasin

17That servant of God, in this one sentence, put together all the arguments required for determining the genuineness of Prophethood. The genuineness of a Prophet can be determined by two things. First, his word and deed; second, his being selfless. What the person meant to say was this: 'First, whatever these people are saying is perfectly reasonable, and their own character also is pure; second, no one can prove that they are calling the people to this faith on account of a selfish motive. Therefore, there is no reason why they should not be listened to." By citing this reasoning of the person the Qur'an set a criterion before the people of how to judge and determine the genuineness of the Prophethood of a Prophet, as if to say; "The word and deed of the Holy Prophet Muhammad (upon whom be Allah's peace and blessings) bear full evidence that he is on the right path. Then, no one can point out any selfish motive or interest behind his struggle of preaching his message. Therefore, there is no reason why a sensible person should reject what he presents.