Short answers, pulled from the story.
In the earliest biblical texts, Satan served as a loyal subordinate and heavenly prosecutor rather than a rebellious enemy of God. The Hebrew term śāton means accuser or adversary, and this celestial being operated entirely within the divine will to test human faithfulness.
During the Second Temple Period, Jewish conceptions of the accuser shifted to a malevolent entity influenced by the dualistic cosmology of Zoroastrianism. This era saw the development of names like Mastema and Satanael, transforming the abstract accuser into a supernatural adversary with abhorrent qualities.
Christianity first explicitly made this connection in the second century AD through the apologist Justin Martyr. Early Church Fathers like Theophilus and Tertullian identified the serpent with Satan, the ancient serpent who deceives the whole inhabited world.
By the 1430s, the Catholic Church began to regard witchcraft as part of a vast conspiracy led by Satan himself. German Inquisitors Heinrich Kramer and Jacob Sprenger argued in their 1487 book Malleus Maleficarum that all sorcery was rooted in the work of Satan.
In Islam, Satan is known as Iblis, an entity made of fire who was cast out of Heaven for refusing to bow before Adam. Iblis claims superiority because he was created from fire while Adam was made from clay, and his sole mission is to lead humanity astray.
Modern Satanism reinterprets Satan as a symbol of liberty, individual empowerment, and the dark evolutionary force of entropy. Atheistic Satanism views Satan as a conceptual framework for human potential, while Theistic Satanism regards him as a real entity and freedom fighter who rebelled against Yahweh.