Who are authorities?

Allah has mentioned to "Slaat" ,"Zakaat" and "Hajj" in Quran.

In Arabic

"Slaat" in general means: to praise, to pray (Do'a),..
"Hajj" in general means: to intent
"Zakaat" in general means: to grow, to purify,...

But Allah has clarified the specific meaning of "Slaat" ,"zakaat" and "Hajj" through prophet's Hadith. . I.e. the prophet(Salaam Be Upon Him&His Progeny) clarified for us what "Slaat" "zakaat" and "Hajj" means: They are certain acts with  specific rules.

For example "Slaat" is such a worshiping act in which you first should perform ablution, then face to Qible, then intend to pray for Allah then say Takbir and ...

So Slaat is different from any other pray(Do'a).

Or Hajj is a special pilgrimage to mecca with  special worshiping acts at a specified time.

The case is the same about "Olel Amr".

Allah has mentioned to it in his Book, Quran.


اعوذ بالله من الشيطان الرجيم
يَأَيها الَّذِينَ ءَامَنُواْ أَطِيعُواْ اللَّهَ وَ أَطِيعُواْ الرَّسُولَ وَ أُوْلىِ الْأَمْرِ مِنكمُ...

4:59
O you who believe! Obey Allah, and obey Rasool, and Olel Amr among you   ...

  In this verse OBEYING Allah and OBEYING Rasool(Salaam be upon him & his progeny) and OBEYING Olel Amr came in the same level without any exception for Olel Amr. I.e. Allah has commanded us to OBEY Olel Amr exactly in the same way we must OBEY Rasool(Salaam be upon him & his progeny) and OBEY Allah. It means this Obedience is an ABSOLUTE OBEDIENCE. 

But which sound wisdom can accept an ABSOLUTE OBEDIENCE for any one (parents, husbands, rulers,…) who are fallible!!!

in Arabic

"Olel Amr" in general means: those who have power to command, authorities

But the prophet(SBUH&HP) has clarified for us the specific meaning of "Olel Amr" and has told us who they are.

It is narrated that Jabir Ansari said when this verse was revealed [4:59 O you who believe! Obey Allah, and obey Rasool, and Olel Amr among you...] we said to the Prophet (SBUH&HP) you introduced Allah and his Rasool [Hadret Mohammad (SBUH&HP)himself] to us. Who is Olel Amr whose obedience has come together with your obedience?

The Prophet (SBUH&HP) said: O' Jabir, Olel Amr are my successors. The first one of them is Ali ibn Abi Taalib then al-Hasan then al-Hosayn then Ali ibn al-hosayn then Mohammad ibn Ali who is well- known in Torat with the name of Baqer.you Jaber will see him. At that time when met him give him my salam. Then al-Sadeq Ja'far ibn Mohammad then Musa ibn Ja'far then Ali ibn Musa then Mohammad ibn Ali then Ali ibn Mohammad then al-Hasan ibn Ali then the one who have the same name and the same Koniye I have, Allah's Hojat in his Earth and his Baqiyat among his servants ibn al-Hasan ibn Ali.

This is the one with whose hand Allah exalted will triumph his Zekr over Easts and Wests of the Earth. This is the one who will be absent from (the sights) of his Shia and his friends. In that occultation no one will remain firm at his Imamat save the ones who Allah has examined their hearts for Iman(faith).

Jabir said I asked: O the prophet of Allah do the Shia benefit from him in his occultation? The prophet(SBUH&HP) said: Yes and swear to God who chose me for prophethood they make use of his light and benefit from his Wilayat in his occultation in the same way as people benefit from the Sun when it is behind the cloud… 

 
(Translated to English from the hadith come in Kamal al-Din wa Tamam al-ne'am V1, P253)