Is it permissible to pray behind an imam who wears amulets, orders the slaughtering and offering of food to children during drought to bring down rain, and makes vows and sacrifices to other than Allah Almighty?

It is permissible to pray behind someone who writes amulets ( tama'im ) from the Qur'an and legitimate supplications, even if hanging them is impermissible. However, if the amulets contain polytheistic elements, one should not pray behind such a person, because vows and sacrifices made to other than Allah constitute shirk (polytheism). It has not been authentically reported from the Prophet, peace be upon him, that he commanded the purchase of a ram or a cow to be slaughtered and eaten by children during drought for the sake of rain. What is prescribed is the Salat al-Istisqa (prayer for rain), supplication, seeking forgiveness, and giving charity. Any act that has no basis in Islamic law is rejected.