It is permissible to pray behind anyone whose prayer is valid for himself.

Therefore, if the Imam of this masjid is a Muslim and doesn’t nullify his Islam, you can pray behind him but if he calls the saints and slaughter to their graves, this is major Shirk and you can’t pray behind him.

If we pray behnid musrik Imam, who believe in grave yards. Is our prayer aceptable?

Prayer | March 24, 2014 7:12 am
Previous

Does saying two takbeers when bowing invalidate the prayer? Do you need to pray prostration of forgetfulness if done so? Because sometimes I get confused with the Takbeer of the imam and the one who repeats the takbeer thus I may say two takbeers whenbowing by mistake
Next

In the masjid it is full so sometimes on a different floor (in the masjid hallway) a few brothers make a line and follow the imam. They can’t see the imam and the lines are not joined to the one another. Is the prayer valid