What is the ruling on one who prayed 'Isha' in one mosque and tarawih or tahajjud in another? Is he considered to have stood with the imam?

Question : The question is about one who prayed 'Isha' in one mosque and tarawih or tahajjud in another, whether with the same imam or not? Is he considered to have stood with the imam until he leaves?

Answer : It appears that if one stands with the imam until he leaves in tarawih, even if he did not pray 'Isha', he is credited with standing the night. If there is tahajjud, he must be with him in the tahajjud as well. Yes. If he concludes the tarawih with witr, it means he has finished.