The ruling on a traveler praying behind an imam who is praying Maghrib
Machine translationRead the Arabic original
Question:
If the imam is praying Maghrib and I am traveling, and I want to pray 'Isha' behind him, does that mean I have prayed Maghrib?
Answer:
If he is praying Maghrib and you have not prayed Maghrib, you pray with him. But if you are a traveler and you join him, and you have already prayed Maghrib, and you find him praying Maghrib—let us assume this, because this question is actually hypothetical—if we assume that you have prayed Maghrib and then you find him, meaning he has entered the Maghrib prayer, you join him at the beginning. When he stands for the third rak'ah, you sit down. When he says the taslim, you say the taslim with him. You have the intention of 'Isha', and he has the intention of Maghrib.
If the imam is praying Maghrib and I am traveling, and I want to pray 'Isha' behind him, does that mean I have prayed Maghrib?
Answer:
If he is praying Maghrib and you have not prayed Maghrib, you pray with him. But if you are a traveler and you join him, and you have already prayed Maghrib, and you find him praying Maghrib—let us assume this, because this question is actually hypothetical—if we assume that you have prayed Maghrib and then you find him, meaning he has entered the Maghrib prayer, you join him at the beginning. When he stands for the third rak'ah, you sit down. When he says the taslim, you say the taslim with him. You have the intention of 'Isha', and he has the intention of Maghrib.
Source
تفسير ايات الاحكام -22 — af.org.sa (8:36)
The Arabic text is a machine transcription of the audio recording.