Theistic Satanism, otherwise referred to as religious Satanism, spiritual Satanism, or traditional Satanism, is an umbrella term for religious groups that consider Satan, the Devil, to objectively exist as a deity, supernatural entity, or spiritual being worthy of worship or reverence, whom individuals may contact and convene with. This is in contrast with the atheistic archetype, metaphor, or symbol found in LaVeyan Satanism, who sometimes dismiss Theistic Satanist worship of devils as a "Christian heresy".

Satan, also known as the Devil, and sometimes also called Lucifer in Christianity, is an entity in Abrahamic religions that seduces humans into sin or falsehood. In Judaism, Satan is seen as an agent subservient to God, typically regarded as a metaphor for the yetzer hara, or "evil inclination". In Christianity and Islam, he is usually seen as a fallen angel or jinn who has rebelled against God, who nevertheless allows him temporary power over the fallen world and a host of demons. In the Quran, Shaitan, also known as Iblis, is an entity made of fire who was cast out of Heaven because he refused to bow before the newly created Adam and incites humans to sin by infecting their minds with waswās.