So when he clearly states that the AhlulBayt are from him...

So when he clearly states that the AhlulBayt are from him, it indicates the grand level of piety and excellence which these members of the household have attained such that they have earned the reward of being “from the Prophet”. No other person was given that honor among the companions of the Prophet (SA) except Salman Al Muhammadi who was an agent and trustee to the AhlulBayt (SA) to the end of his life-time and whose affinity to them was such that he was attached to them.

His superior station was such that Prophet (SA) said in his regards, “Salman is from us, AhlulBayt.” (Sunan ibn Majah, Al Mustadrak, Musnad Ibn Hanbal) This does not mean that he is one of them, but rather “from them” and associated to them.

In fact, this honor of being “from the Prophet and his AhlulBayt” can also be attained by the pious believers as Imam Al Redha (AS) said, “Our Shia are from us, they were created from the remainder of our clay.” Furthermore, if a person is told that they belong to and come from the same origin as a very esteemed and honorable personality or a saint whom they recognize their excellence in actions and behavior, it naturally encourages them to beautify themselves furthermore with the ornaments of good morals and virtues and certainly nothing from the ill traits and negative characteristics.

This may be a good reason why many of the children and progeny of the Prophets and Imams try to stay away from committing any wrong or inappropriate act since they recognize that their origin dictates that they act according to their noble ancestry and behave in their best possible conduct.

Although the purified AhlulBayt (AS) are themselves a beacon of light and are in no need of encouragement, one can imagine that this declared association between them and the Prophet further intensifies their existing love and desire to abide by the perfect code of values and behavior such that they practically achieve the status of being “from the Prophet”.

As explained in the book Min Fiqh Al Zahra by Imam Mohammad Al Husaini Al Shirazi, it is possible that one meaning intended by the words “They are from me and I am from them” is for Allah (SWT) to convey the point that He (SWT) created the AhlulBayt (AS) and brought them into existence for the sake of the Prophet.