Firstly: Shia Muslims vary in their beliefs and levels of adherence to Shia practices. The general principle is that Shia Muslims are considered part of the Muslim community and are followers of Islam, unless the following conditions are established:
1- If the person is from the Batiniyya sect, who hold interpretations that contradict the clear and authentic teachings of the Quran, like the Nusayris and Ismailis, the majority of scholars have declared them disbelievers (kafirs). In this case, it would not be valid to pray behind them.
2- If the Shia individual is from the Imamiyya sect but goes to extremes regarding Ali or Hussein, elevating them beyond their rightful status and placing them on the level of prophethood, then it would also not be permissible to pray behind them.
3- If the Shia individual is from the Imamiyya sect but engages in insulting the companions of the Prophet or questioning their integrity, or if they disparage the Mothers of the Believers, then if they are knowledgeable, they will be described as disbelievers by denying the Quran which describes these companions as truthful and successful. In this case, it is not permissible to pray behind them.
If the person is ignorant, it is not recommended to pray behind them, as they are following a misguided innovation without any doubt or plausible interpretation. Although their ignorance might prevent them from being classified as disbelievers, it still places them outside the accepted realm of Imamate and acceptance.
Secondly: If the Imam is a Shia, but his specific beliefs are concealed, meaning we do not know which particular view he holds, the default assumption is that the prayer behind him is valid, as a precaution based on the fundamental principle of Islam, which remains intact until proven otherwise.
His omission of the final salutation (Tasleem) does not invalidate the prayer, as there is a difference of opinion among Sunni scholars regarding the ruling on the final salutation in the prayer:
– The majority of jurists from the three schools of law, namely the Maliki, Shafi’i, and Hanbali, agree that exiting the prayer can only occur through the final salutation (Tasleem). If someone exits the prayer before performing the final salutation, their prayer becomes invalid. This is based on the understanding that the final salutation is a fundamental component of the prayer and a pillar that is fulfilled with one Tasleem, while the second Tasleem is recommended.
– The Hanafi school of thought holds that offering the final salutation (Tasleem) at the end of prayer is obligatory, and omitting it necessitates the performance of the prostration of forgetfulness (Sujood as-Sahw). However, leaving out the Tasleem does not nullify the prayer; one can exit the prayer through the Tasleem, breaking one’s ablution (wudu), or simply departing after the Tashahhud. If someone does this unintentionally, there is no sin upon them, and they perform the prostration of forgetfulness. If someone intentionally avoids the Tasleem, their prayer remains valid but it carries a certain level of misconduct.
– Thirdly: In the Imami Shia school of thought, the final salutation (Tasleem) is obligatory based on the stronger opinion, and it is an integral part of the prayer. Therefore, in this context, everything required for the validity of the prayer, such as facing the Qiblah, covering the private parts, being in a state of ritual purity, and others, are obligatory during the Tasleem. The Tasleem serves as the exit point from the prayer and marks the end of its restrictions, allowing for actions otherwise forbidden. It is not considered a pillar (Rukn) of the prayer. Intentionally omitting the Tasleem renders the prayer invalid while omitting it as an act of forgetfulness does not render it invalid. If one forgets the Tasleem and later remembers after performing actions that invalidate the prayer intentionally or forgetfully, or after the passage of the time for reciting the Tasleem, there is no obligation to make up for it. However, they should perform the two prostrations of forgetfulness for the deficiency caused by omitting it. If they remember before those circumstances, they should complete the Tasleem without any additional actions, unless they spoke, in which case they should perform the two prostrations of forgetfulness, sit down, and ensure tranquility.
Fatwa by Dr. Khālid Naṣr