If i recite mistakenly Sura Fathiha instead of Aththahiyath or If I recite mistakenly Aththahiyath instead of Sura Fathiha, what should I do? In this situation do I have to do "Sajadha Shah" or Do I have to repeat my prayer again? And if this situation happened when I do Imamadh what I have to do?

All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger.

According to the view we adopt here in Islamweb, the first Tashahhud is an obligation and the final Tashahhud is a pillar of the prayer. Based on this, the ruling on the person who left the first Tashahhud and recited Al-Faatihah instead differs from the person who left the last Tashahhud and recited Al-Faatihah instead. Therefore, if you had recited Al-Faatihah instead of the first Tashahhud, you would have left one of the obligations of prayer. If a person left an obligation unintentionally, then he should make two prostrations of forgetfulness before concluding the prayer by saying Salaam.

But if you had recited Al-Faatihah instead of the last Tashahhud and then you concluded the prayer by saying Salaam, then the prayer is not valid because you have abandoned one of the pillars of prayer. So, if you remembered directly after saying Salaam, you should stand up and perform one Rak’ah instead of the last Rak’ah, but if you remembered after a long period of time, then you are obligated to repeat the whole prayer.

On the other hand, Al-Faatihah is also one of the pillars of prayer in each Rak'ah, so if you recited the Tashahhud instead, and you did not recite Al-Faatihah, then the prayer is not valid. The view we adopt here in Islamweb is that whoever forgets a pillar in a Rak’ah, he should go back to it unless he had already reached the same position from the next Rak’ah. If he had already reached the same position from the next Rak’ah, then he should consider this Rak’ah in lieu of the Rak’ah in which he had forgotten a pillar, so he has to make an extra Rak’ah so that his prayer would be complete.

However, if you remembered after concluding the prayer by saying Salaam that you had forgotten Al-Faatihah, then you should stand up and make up one Rak’ah instead of that Rak'ah, and if there is a long period of time between the time you had concluded the prayer and the time you remembered, then you are obligated to repeat the whole prayer.

The ruling that we have mentioned is the same whether you are an Imaam or you are praying individually. But if there is a long period of time (between the time one has concluded the prayer and the time he remembered) and the prayer is void, then does the congregation have to repeat the prayer? Ibn Hajar Al-Haytami from the Shafi’i School of jurisprudence was asked as per his Al-Fataawa Al-Fiqhiyyah Al-kubra about an Imaam leaving the recitation of Al-Faatihah out of forgetfulness in a loud prayer while the congregation does not know about it and they followed him, do they have to repeat the prayer? And he answered saying: “Yes, they are obligated to repeat the prayer as expressed by their statements [i.e. the statements of the scholars of the Shaafi’i School] as they said if it becomes clear for a person [after he had concluded the prayer] that his Imaam did not say Takbeeratul-Ihraam (saying Allaahu Akbar at the beginning of the prayer) even out of forgetfulness, then the congregation is obligated to repeat the prayer contrarily to when they find out that he only left the intention. That is because leaving out Takbeeratul-Ihraam is an obvious matter, so the congregation would be negligent [if they did not notice it] contrarily to only leaving out the intention. If you consider this, you will find it clear in our issue as Al-Faatihah and Takbeeratul-Ihraam are alike. So if they [the scholars] oblige one to repeat the prayer when leaving Takbeeratul-Ihraam even out of forgetfulness, in the same manner, we will oblige him to do the same when leaving the recitation of Al-Faatihah as it is the same as Takbeeratul-Ihraam because leaving any of them is obvious [and can be easily noticed and known] whether the prayer is loud or silent….. Hence, it is clear that anything that invalidates the prayer and cannot be noticed, like the intention to interrupt the prayer, if it happens, it does not affect the prayer of the congregation, contrarily to what can be noticed even to a certain extent.... So, in case he (the Imaam) leaves out the Takbeeratul-Ihraam or Al-Faatihah and there are indications to prove that he left it and the congregation does not have a sound reason for not knowing about what invalidates the prayer, so the person being led in the prayer is negligent and he is obligated to repeat the prayer.”

Anyway, the scholars have three opinions in regard to the connection between the prayer of the congregation and the prayer of the Imaam, which Ibn Taymiyyah mentioned and we will summarize them in the following:

1- There is no connection between the two, i.e. between the prayer of the Imaam and the prayer of the congregation in the sense that every person prays for himself; the benefit for the congregation is just to multiply the reward by performing the prayer in congregation. The evidence for this is the saying of the Prophet about the Imaams: "If they (those who lead the congregation) do good (are right and did not make a mistake), then this is good for you and for them (i.e. you get the reward and they get the reward), and if they make a mistake, then your prayer is valid (you get the reward) and it is they who are responsible and accountable for their mistake.”

2- The prayer (of the congregations) is based on the prayer of the Imaam and it is absolutely part of it, and any mistake that happens in the prayer of the Imaam applies to the prayer of the congregation as the Prophet said: ''The Imaam is a guarantor.” This is the view of Abu Haneefah and a narration of Ahmad that is chosen by Abul-Khattaab.

3- The prayer is based on the prayer of the Imaam but the deficiency applies to the prayer of the congregation if there is no excuse for each of them, but if there is a sound excuse, then the deficiency does not apply... This is the view of Maalik, Ahmad and others. Therefore, the statements of the Companions on this matter apply to it, and they are the moderate statements.... The evidence about the correctness of this statement is that Al-Bukhari reported in his Saheeh that Abu Hurayrah narrated that the Prophet said: ''They pray for you, if they are right (i.e. they do not make a mistake), then you get the reward and they get the reward, and if they make a mistake, then your prayer is valid and it is their prayer that is deficient.”

Allaah Knows best.