Moreover...
Moreover, according to reliable sources, he is reported to have also said: We are the group whose obedience has been made obligatory for all by the Creator of the universe, and He has allotted booty (Anfal) to us, that is, the produce of all mountains and lands etc which has been mentioned at relevant places.
(Sura Nisa:54) Likewise, it is reported by Husain bin Alaa that he said: I presented the beliefs of the Shias to Imam Sadiq (a.s.) that the obedience of legatees has been made obligatory by Allah. The Hazrat said: Yes, the legatees are the people about whom Allah has ordained: Obey Allah and obey the Messenger and those vested with authority (Ulil Amr) among you.
(Sura Maida 5:55) All have agreed among Shias and Ahle Sunnat that none except Amirul Momineen (a.s.) has ever paid Zakat (sadaqah-alms) while bowing in Prayer and, according to some narrations, this giving of alms while bowing down (in Rukoo) is a clear reference to the holy Imams and the use of plural sign (those) is in support of it. It is narrated according to reliable chains of narrators that a man from Fars asked Imam Ridha (a.s.): Is your obedience compulsory? He said: Yes.
He asked: Is it obligatory as was the case with Amirul Momineen (a.s.). He replied: Yes. Again, according to reliable sources, Abu Baseer has reported that he asked Imam Ridha (a.s.): Are all the Imams (a.s.) like one person in the matter of Imamate and is the obedience to them compulsory? Does the command apply to all of them? He replied: Yes.