The Superiority and Infallibility of the Household of the Prophet in Verse and Ahadith of Salavat

A number of Quranic verses and Ahadith express the superiority and infallibility of the household of the prophet from which is the verse of Salavat (al-Ahzab: 56) and Ahadith concerning it. This verse of Quran explains that the Prophet of God (peace be upon him) is blessed by God and his angels. Also, following God and his angels, it is requested from faithful people to bless the Prophet of God. It is questioned from the Prophet of God, in a number of Ahadith, as to how to bless him, and the Prophet answered: say "O Allah, bless Muhammad and the household of Muhammad". This Hadith suggests the Household of the prophet has such status, in existential perfections, that they share prophet in particular divine blessing. From other hand, there is no doubt in infallibility and superiority of the Prophet than others. So the household of the prophet have the same characteristic. However, this sharing does not contract with superiority of the prophet than everyone even his household, since attributes of perfection have gradations, as well as this rule runs on prophets of God.