Is there a religion that believes in both satan and god?

Satan was one of the angels. His name means "father of the lie". He became jealous of humans and of worship to God. He and those angels who followed him, the demons, the Bible says "forsook their natural dwelling place and took on bodies of humans" to satisfy their unatural desires. A universal issue had also been raised afterwards. Satan challenged Gods right to rule. He told God that people only worshiped Him as long as He gave them everything and not because they loved Him. So, satan said if God were to not let us be so blessed, so to speak, that humans would turn their backs on Him. This challenge is still going on in our day and is soon to be settled once and for all. Satan has been allowed to try to prove his challenge. The true christians have maintained their integrity to God even to death. Others have not and never will. Mankind has had more than enough time to see if they could rule themselves without God. Man has failed miserably. God will not forget our loyalty and many blessings await us after Armageddon for our endurance and faith in Him.