Immortality of the soul in the context of "Ancient Mesopotamian religion"

Middle Platonism is the modern name given to a revival and outgrowth of Platonic philosophy, lasting from about 90 BC – when Antiochus of Ascalon rejected the scepticism of the new Academy – until the development of neoplatonism under Plotinus in the 3rd century. Middle Platonism absorbed many doctrines from the rival Peripatetic and Stoic schools. The pre-eminent philosopher in this period, Plutarch (c. 45–120), defended the freedom of the will and the immortality of the soul. He sought to show that God, in creating the world, had transformed matter, as the receptacle of evil, into the divine soul of the world, where it continued to operate as the source of all evil. God is a transcendent being, who operates through divine intermediaries, which are the gods and daemons of popular religion. Numenius of Apamea (c. 160) combined Platonism with neopythagoreanism and other eastern philosophies, in a move which would prefigure the development of neoplatonism.

The concept of an immaterial and immortal soul—distinct from the corporeal body—did not appear in Judaism before the Babylonian exile, instead developing as a result of interaction with Persian and Hellenistic philosophies. Accordingly, the Hebrew word נֶ֫פֶשׁ‎ (nephesh)—though translated as "soul" in some older English-language Bibles—actually has a meaning closer to "living being". Nephesh was translated into Greek in the Septuagint as ψυχή (psūchê), using the Greek word for "soul". The New Testament also uses the word ψυχή.

The textual evidence indicates a multiplicity of perspectives on souls, including probable changes during the centuries in which the biblical corpus developed.

Christian mortalism is the Christian belief that the human soul is not naturally immortal, and may include the belief that the soul is "sleeping" after death until the Resurrection of the Dead and the Last Judgment, a time known as the intermediate state. "Soul sleep" is often used as a pejorative term, so the more neutral term "mortalism" was also used in the nineteenth century, and "Christian mortalism" since the 1970s. Historically the term psychopannychism was also used, despite problems with the etymology and application. The term thnetopsychism has also been used; for example, Gordon Campbell (2008) identified John Milton as believing in the latter.

Christian mortalism stands in contrast with the traditional Christian belief that the souls of the dead immediately go to heaven, or hell, or (in Catholicism) purgatory. Christian mortalism has been taught by several theologians and church organizations throughout history, while also facing opposition from aspects of Christian organized religion. The Catholic Church condemned such thinking in the Fifth Council of the Lateran as "erroneous assertions". Supporters include eighteenth-century religious figure Henry Layton, among many others.