The ruling on one who enters the mosque while the imam is praying tarawih and has not yet prayed the obligatory prayer

Question : If one enters the mosque while the imam is praying tarawih and has not yet prayed the obligatory prayer, what should he do? May Allah reward you with good.

Answer : If you enter the mosque and the imam is praying tarawih, and you have not yet prayed the obligatory prayer, enter with the imam with the intention of the obligatory prayer. If you catch the imam from the first rak'ah, then when he concludes the prayer, perform two rak'ahs. If you catch him in the second rak'ah, then when he concludes the prayer, perform three rak'ahs. The important thing is that you enter with the imam, even if the imam is praying a voluntary prayer and you are praying an obligatory one. Imam Ahmad (may Allah have mercy on him) explicitly stated this issue and said: If one enters while they are in tarawih and has not prayed 'Isha', let him enter with them with the intention of the 'Isha prayer, then complete the remainder of his prayer.