The existence of God is one of the most important issues in the first philosophy. The necessary being is a being whose existence is not dependent on anything else and the creation argument is the argument that the existence of God is proved by the existence of his creation, and this is a kind of dependence for proving the existence of God, and creation is separate from God, so we must accept that something other than God is involved in proving the existence of God. But philosophers, have noticed that it is better if the proof of the existence of God does not depend on something else, but relies solely on himself. Therefore, since his existence is not based on his creation, it is better if his proof is not based on his creation. This type of argument has been called the the argument of the truthful and Ibn Sina claims that he has interpreted such an argument; Because the objective existence, which denies sophistry, is either obligatory or possible, and in both cases it is proved to be obligatory, and on this basis it claims that its argument is the argument of the truthful; Because the proof of God's existence is not based on something else- that is, his creation. But Mulla Sadra, emphasizing the correctness of Ibn Sina's argument, does not consider it to be the argument of the truthful. The present article, based on the analysis of Ibn Sina's argument and the analysis of Mulla Sadra's critiques, shows why Ibn Sina's argument is not the argument of the truthful from the point of view of Mulla Sadra. Therefore, the range of arguments that have followed Ibn Sina's argument is not the argument of the truthful. Of course, these arguments are superior to the creation argument, and therefore, according to Mulla Sadra, Ibn Sina's argument is close to the method of the argument of the truthful. In the end, we will mention why Mulla Sadra's argument is true.