That when you are saying prayer behind an imam, who is a local imam, you are not permitted to halve your prayer. You must do it to the full because you are a follower of the imam and this is the overruling constitution, which overrides every other constitution. So after the prayer, having finished, you are still permitted not to say your sunnahs, which you normally say during your certain times.
But if you join an imam’s prayer, even if you have said one dhikr behind him, while he has already performed three, after he has said salam, you are not permitted to finish the prayer after one more rakat, because you are permitted. You follow the imam’s prayer to the full, that is, you will say three more rakats after finishing one rakat with the imam. So that is the overriding constitution and that should be an exception made to the general rule I have explained.
There is another aspect to this. If the imam is on journey and he reduces his prayer and the followers are local, then the locals stand up and say their remaining prayer to the full. They are not given the benefit. Yes, thank you for pointing out. They are not given the benefit of imam’s personal permission. You know, if that were so, people will always be in the search of imams from those who are travelling, you know.
