Entering the 'Isha' prayer with the imam with the intention of Maghrib

The questioner:
If a person joins the congregation for the 'Isha' prayer without having prayed the Maghrib prayer, intending that it is the Maghrib prayer, what should he do?

The Shaykh:
If he joins with the intention of Maghrib and the imam is praying 'Isha', when the imam stands for the fourth rak'ah, he sits down. He sits down and recites the tashahhud. If he wishes, he may say the taslim, or if he wishes, he may wait for the imam to say the taslim and say it with him. However, he must not follow the imam in the fourth rak'ah. It is permissible for him to follow while maintaining his intention, and his Maghrib prayer is valid based on his intention, but he must not stand up for the fourth rak'ah. Yes. Yes.

Another questioner:
And he will be with you and teach you.

The Shaykh:
There is no harm, there is no harm at all, but you are with them in the fourth rak'ah. Yes.

The presenter:
Yes. Yes.