After all...
After all, it is the Qur’an which testifies to their spiritual purity of the highest form by saying: “Verily Allah intends to purify you, O the Ahlu ‘l-bayt, a thorough purification.” (33:33) Combine this verse about the Ahlu ‘1-bayt’s purity with the following: “It is the holy Qur’an in a preserved tablet, none shall touch it but the purified ones.” (56:79) The real sense of this verse is that the Qur’an which is “in a preserved tablet” is not accessible to anyone except those who are purified by Allah.
This shows that the Ahlu ‘1-bayt could understand the Qur’an better than any other Muslim. It is for this very reason that Allah commanded His Messenger to ask the people to love his Ahlu 1-bayt: Say (O Muhammad), ‘I do not ask from you any reward (for teaching Islam to you) except to love my near ones.’ (42:23) This love was made obligatory because it would automatically entail obedience of those whom one loves.
If the Ahlu ‘1-bayt were not truthful, reliable, and worthy of following, would Allah command us to love them? These few verses of the holy Qur’an are enough to show that the best commentators of the Qur’an and the most authentic source for the Prophet’s sunna are the Imams of Ahlu ‘1-bayt. The Prophet himself said, “I am leaving among you two worthy things. As long as you hold fast on to them both, you will never go astray after me.
One is greater than the other: the Book of Allah (which is a rope suspended from the heaven to the earth) and my descendants, my Ahlu ‘1-bayt. They will not separate from each other until they come to me at the (fountain of) Kawthar (in the hereafter). Therefore, see how you recompense me by the way you deal with them.” This is not the place to discuss the authenticity of this hadith, but it will suffice to quote Ibn Hajar al-Makki, a famous Sunni polemicist.
After recording this hadlth from various companions who had heard it from the Prophet at various places and times, Ibn Hajar says, “And there is no contradiction in these [numerous reports] since there was nothing to prevent the Prophet from repeating [this statement] at those various places because of the importance of the holy Book and the pure Family.”2 We can conclude from these verses and the hadith mentioned above that the Ahlu 1-bayt are the divinely appointed commentators of the Qur’an, and the most authentic and the best source for the sunna.
It is for this reason that we prefer them to all other sources.