Theologically the term has been variously interpreted:

(1) The doctrine that the universe was created by God out of nothing, or (in recent years) that the world was created a few thousand years ago, in opposition to the view that it is several thousand million years old.

(2) The doctrine that species were created, in opposition to the evolutionary view.

(3) In Catholic theology, the doctrine (held by Jerome, Hilary, Aquinas, and others, as well as Calvin), that God creates from nothing each new soul that comes into the world, in contrast with the Traducian view (held by Tertullian, Luther, and others) that souls are formed naturally as the body develops, or that they are reincarnated after previous existences on earth (metempsychosis). Augustine suspected that Creationism and original sin were incompatible, for a new creation by God cannot be tainted with sin. Nevertheless, orthodox Catholicism holds to Creationism, Aquinas insisting that its denial is heretical. In medieval theology the soul's creation occurred on the fortieth day after conception for a male, on the eightieth for a female.