Question: I had previously asked you about the ruling on the validity of praying behind an Imaam (leader of congregational Prayer) who commits Shirk (associating others with Allaah in His Divinity or worship) while claiming to be a Muslim, such as those who offer sacrifices to Awliya’ (pious people), invoke them, make vows to them, circumambulate around their graves, set out to visit them and so on.We are frequently asked about this issue during our travels to some Muslim countries, and it was repeatedly posed by Ansaar (Supporters) of Sunnah in Sudan when we went there earlier this year. You recommended that we send you this question in writing, to be viewed by the Iftaa’ Committee and the answer be discussed in detail and then published. Again, I am reminding Your Eminence, and waiting for your written reply in detail. May Allaah reward you the best for your efforts.
Answer: If a person makes vows or offers sacrifices to other than Allaah; or invokes other than Allah for something beyond normal means, such as healing the sick or having progeny; or invokes people who are absent to relieve a distress, or someone dead to repel harm; circumambulates graves; set out on a special journey to them; or seeks the help of idols and similar objects, they are considered Mushrikoon (those who associate others with Allaah in worship), guilty of major Shirk… read more here.