Is it permissible to offer Salah

Q 2: is it permissible for a person to offer Salah (Prayer) behind an Imam who commits acts of Bid`ah (innovation in religion)?

A: If you know an Imam who does not commit acts of Bid`ah, then you should pray behind him instead of an Imam who commits Bid`ah. If you do not know anyone except the Imam who commits acts of Bid`ah, you have to advise him, he may abandon his Bid`ah. If you advise him then he does not accept your advice and his Bid`ah involves acts of Shirk (associating others with Allah in His Divinity or worship) such as seeking help from the dead, (Part No. 7; Page No. 365) supplicating to the dead instead of Allah, or slaughtering for their sake, then it is not permissible to offer Salah behind him as he is considered a Kafir (disbeliever) and his Salah as well as the Salah of the people behind him is invalid.May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.