Ok, but is it not the same thing, shia follow the fallible jurists like sunni’s so they have few school of law  sects like Sisitani, khoei, khorasani khamenei ? if the source is infallible why we have these schools to follow of islamic acts they were not all issues  clarified by imams.

mehdi Staff answered 55 mins ago

أعوذ بالله من الشيطان الرجيم
بِسْمِ ٱللَّٰهِ ٱلرَّحْمَٰنِ ٱلرَّحِيمِ
As Salaamu Alaikum Wa Rahmatullahi Wa Barakatuh,
We hope this answer reaches you in good health and Islamic spirit.
Based on your specific question and information provided.
Fundamental or Principles of Faith ( Belief ) are.

1. Tawhid ( Divine Unity ).
2. ‘Adl ( Divine Justice ).
3. Nabuwwat ( Prophethood ).
4. Imamat ( The Divine Leadership ).
5. Ma’ad ( The Return ).

The Shi’ahs believe that the divine leaders of the Muslims after Muhammad al-Mustafa ( Peace be upon him and his pure Progeny)  are the Twelve Infallible Imams (as) and that Muhammad al-Mustafa ( Peace be upon him and his pure Progeny)  specified them as:

1. Al-Imam ‘Ali ibn Abu Talib, Commander of the Faithful [Amir al-Mu’minin] (as)
2. Al-Imam al-Hasan ibn ‘Ali, the Oldest Grandson [al-Sibt al-Akbar] (as)
3. Al-Imam al-Husayn ibn ‘Ali, Master of the Martyrs [Sayyid al-Shuhada’] (as)
4. Al-Imam ‘Ali ibn al-Husayn, Beauty of the Worshippers [Zayn al-’Abidin] (as)
5. Al-Imam Muhammad ibn ‘Ali, the Splitter of Knowledge [al-Baqir] (as)
6. Al-Imam Ja’far ibn Muhammad, the Truthful [al-Sadiq] (as)
7. Al-Imam Musa ibn Ja’far, the Controller of anger [al-Kadhim] (as)
8. Al-Imam ‘Ali ibn Musa, the Content [al-Rida] (as)
9. Al-Imam Muhammad ibn ‘Ali, the Generous [al-Jawad] (as)
10. Al-Imam ‘Ali ibn Muhammad, the guide [al-Hadi] (as)
11. Al-Imam al-Hasan ibn ‘Ali, the Soldier [al-’Askari] (as)
12. Al-Imam al-Hujjat ibn al-Hasan al-’Askari, the Rightly Guided, the Awaited [al-Mahdi ] (as)

Our Islamic laws / Jurisprudence is based on the Qur’an and the Tradition / Hadith of Muhammad al-Mustafa (Peace be upon him and his pure Progeny) transmitted to us thru the Twelve Infallible Imams (as).  It is necessary for a Muslim to believe in the fundamentals of faith on the basis of proof and he cannot follow anyone in this respect i.e. he cannot accept he word of another with regard to the fundamentals without demanding proof. However, to act on Islamic code (except in those matters which are considered by all to be indisputable e.g. the obligatory nature of the five daily prayers, fasting during the holy month of Ramadan etc.) a person must  be Jurist or follow one of the Most Learned Jurist ( Taqlid ).
I have provided general information. You can speak to the  qualified Islamic Scholars  in person or refer to the various books by qualified Islamic Scholars on Principles of Faith ( Usual al-Din) / Aqeeda or  Tafsir / Exegesis of the Holy Qur’an or  Nahj al-Balagha or Ziyarats ( for example – Ziyarat Warisa).
You can read about what other Muslims believe in the books written by them. The word “Imam” for us means the Divinely Appointed Leaders ( Imams ).  Other Muslims use the word Imam for the fallible Jurists ( The learned in Islamic law from their sources), or Collectors of Hadith / Tradition. The sects among the other Muslims are named after and based on their following a Jurist (fallible person who is learned in Islamic law). They are  divided into four  Main schools of law or fiqh (religious jurisprudence): Hanafi, Shafi, Maliki and Hanbali.
اَللّٰهُ أَعْلَم‎
(and Allah(awj) Knows best)
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