What is the ruling on one who changes his intention from Witr to 'Isha' during the prayer?

The Shaykh : We mentioned, my brother, we mentioned that it is connected to five matters.

The questioner : The dispensation. What is being thought about.

The Shaykh : No, you honored us with the name, my brother.

The questioner : Straightforward.

The Shaykh : Yes.

The questioner : The questioner says: I missed the 'Isha' prayer and did not catch the prayer, and I did not catch anything but one rak'ah of the Witr, so I prayed with him with the intention of Witr. Then I remembered during the prayer that I had not prayed 'Isha', so I intended it for 'Isha'. When the imam finished the taslim, I completed three rak'ahs. Is the prayer valid? Do I have to repeat it?

The Shaykh : The question is being heard now. This is a man who entered the prayer with the imam intending it to be Witr, then he remembered that he had not prayed 'Isha', so what should he do? Look at this word. Yes, you are missing us. The question is clear, may Allah bless you. He entered with the intention of what? Witr, then he remembered that he had not prayed 'Isha', so he changed it to 'Isha'. Is that valid? The answer is that it is not valid. Because we have rules: changing from a specific prayer to a specific prayer is not valid, and changing from a general prayer to a specific prayer is not valid. But changing from a specific prayer to a general prayer is valid. Pay attention, everyone. In prayer, changing from one prayer to another: changing from a specific to a specific is not valid. Changing from a general to a specific is not valid. Changing from a specific to a general is valid. Is that clear? Good. The example of changing from a specific to a specific: a person enters the 'Asr prayer, then he remembers that he prayed the Zuhr prayer without ablution, so during the prayer he changes the 'Asr to Zuhr. Is that valid or not? It is not valid. Why? Teacher. Teacher. Because it is from a specific to a specific. And the reason it is not valid is that a specific act of worship must be intended from the very beginning, before entering it. As for during it, it means that the part prior to the new intention occurred without being intended. And the Prophet (peace and blessings be upon him) said: Good. In the example I just mentioned, he entered with the intention of 'Asr, then he remembered that he prayed Zuhr without ablution, so he changed it to 'Asr? He changed it to Zuhr. Which one is valid? Neither is valid. Neither Zuhr nor 'Asr is valid. 'Asr is not valid because it was invalidated by his changing it to Zuhr. And Zuhr is not valid because he did not intend it from the beginning. And based on this, we say that this change is not valid.
Good. Changing from a general to a specific, from a general to a specific. For example, a man stands to pray a voluntary prayer, praying two rak'ahs as voluntary for Allah the Exalted, then he remembers that he did not pray Fajr, so he intends it to be the Fajr prayer. It is not valid. Why? Because he changed from a general to a specific, and a specific prayer must be intended from its beginning. Good. Changing from a specific to a general is valid. For example, a man enters to pray with the intention of Fajr, for instance, then he changes it to make it a Sunnah. Which Sunnah? It is not a regular Sunnah (Ratibah), because the Ratibah is specific, but it is a general Sunnah. Like this. It is valid. Why? Because the intention of a specific prayer actually includes two intentions: the intention of the general prayer and the intention of specifying it. So if he drops the intention of specifying it, what remains? The general prayer remains. Pay attention. So this man who changed the intention of the obligatory prayer, which is Fajr, to a general voluntary prayer, we say this is correct. Because the intention of the obligatory prayer includes both specifying and generalizing. So if he cancels the specifying, the generalizing remains.
And based on this, we look at the issue the questioner asked about. This questioner entered with the imam with the intention of Witr, then he remembered that he had not prayed 'Isha', so he changed the intention to the 'Isha' prayer. Is it valid or not? It is not valid. And based on this, the questioner must, if he is hearing what we are saying, he must repeat the 'Isha' prayer. And he should hasten now before the time for 'Isha' ends, because the time for 'Isha' ends when the night is half over. Now? Good. Yes, yes.
What is your opinion if he entered with the imam and found the imam praying Tarawih, and he entered with him with the intention of 'Isha'? Abu 'Abdullah. It is valid. It is valid to enter with him with the intention of 'Isha'. We know the world from before.
Because he formed the intention from before. And the correct view is the permissibility of a person who has an obligation following a person who is praying voluntary prayer. And Imam Ahmad (may Allah have mercy on him) explicitly stated this issue, meaning the permissibility of a person praying the 'Isha' prayer behind one who is praying the Tarawih prayer. If the person is a traveler, his prayer becomes two rak'ahs. If he entered with the imam in the first rak'ah of Tarawih, he says the taslim with him. And if he entered in the second rak'ah, he completes one rak'ah. As for one who is required to complete the prayer, if he entered with the imam in the first rak'ah of Tarawih, he completes two rak'ahs after them. And if he entered in the second, he completes three rak'ahs.