This article has dealt with and evaluated the Mu'tazilite rational answers to the objections which have been put forward to the prophethood by some heretical groups as Barahima. These objections and answers have been dealt with and evaluated in five groups. The aim of this subject is to recognise the Mu'tazilite opinions of the rational bases of the prophethood and to be able to see the dimensions and the methods of the Mu'tazilite rationalism.