The infallibility of the prophets is one of the fundamental beliefs in Islam and among Muslims. According to Shiite beliefs, the prophets are innocent of any sin (major, minor, in private, public, wrong and in general any slip) that causes a person to lose trust in the Holy Prophet (PBUH (. Shiite scholars have relied on the "trust" concept to explain this important opinion. They believe that the reason for "trust" (with various interpretations) has the proper ability to explain the claim of infallibility in all its instances. But also, in order to elucidate the "infallibility of the Infallibles", the Shiites must also resolve the contradiction between the rational arguments and the appearances of the verses of the Qur'an, which in a way indicate the infallibility of the some prophets.

This article examines the issue using the narrations of the Ahl al-Bayt and the analytical method of interpreting the verses of the Holy Quran by other verses, as well as the rational scheme in responding to the mentioned contradiction. This study also analyzes the argument of another article that bases its explanation on the concept of “failure to do the better”. As a result, it seems that the author of the mentioned article did not have a correct understanding of the “failure to do the better”, because he considered the “failure to do the better” to be equivalent to omitting a highly regarded deed, while “failure to do the better” from the prophets is not appropriate. Nevertheless, the action of Prophet Adam (pbuh) can also be interpreted as a formative sin and not the “failure to do the better”.