Ali ibn Moosa al-Rida, Muhammad ibn ‘Ali ibn Moosa al-Jawaad, ‘Ali ibn Muhammad ibn ‘Ali al-‘Askari, and al-Hasan ibn ‘Ali ibn Muhammad al-‘Askari. Concerning them, Shaykh al-Islam (Ibn Taymiyah) said: They did not show a great deal of knowledge such that the ummah might benefit from them, nor did they have any authority by means of which they could help the ummah. Rather they were like any other Haashimis, they occupy a respected position, and they have sufficient knowledge of what which is needed by them and expected of people like them; it is a type is knowledge that is widely available to ordinary Muslims. But the type of knowledge that is exclusive to the scholars was not present in their case. Therefore seeks of knowledge did not receive from them what they received from the other three. Had they had that which was useful to seekers of knowledge, they would have sought it from them, as seekers of knowledge are well aware of where to go for knowledge. Minhaaj al-Sunnah (6/387).