The doctrine of the serpent seed, also known as the dual-seed or the two-seedline doctrine, is a controversial and fringe Christian religious belief which explains the biblical account of the fall of man by stating that the Serpent mated with Eve in the Garden of Eden, and the offspring of their union was Cain. This event resulted in the creation of two races of people: the wicked descendants of the Serpent who were destined for damnation, and the righteous descendants of Adam who were destined to have eternal life. The doctrine frames human history as a conflict between these two races in which the descendants of Adam will eventually triumph over the descendants of the Serpent. Elements of the teaching appears in the early Gnostic writings of Valentinus (100–160) and the Gospel of Philip (). Mainstream Christian teachers rejected the serpent seed doctrine as heresy during the gnostic period. Irenaeus (), an Early Church Father, described the gnostic doctrine that the original sin was adultery between Eve and the serpent and explicitly rejected it as heresy in his book Against Heresies. In the middle ages, the concept also appeared in Jewish literature, including the Targum Pseudo-Jonathan. During the 19th century, the serpent seed doctrine was revived by American religious leaders who wanted to promote white supremacy. The modern versions of the serpent seed doctrine were developed within the teachings of British Israelism by C. A. L. Totten (1851–1908) and Russel Kelso Carter (1849–1928). Daniel Parker (1781–1844) was also responsible for reviving and promoting the doctrine among Primitive Baptists. Teachers of Christian Identity Theology, which branched off from British Israelism, preached the doctrine during the early twentieth century and promoted it within the Ku Klux Klan, Aryan Nations, the American Nazi Party and other white supremacist organizations. The belief's adherents commonly use it to justify antisemitism and racism by claiming that Jews or members of non-white races are the descendants of Cain and the Serpent, who they variably interpret to be Satan or an intelligent non-human creature which lived before Adam and Eve. The serpent seed teaching comes in several different forms. William M. Branham (1909–1965), Arnold Murray (1929–2014), Wesley A. Swift (1913–1970), and Sun Myung Moon (1920–2012) played important roles in spreading different versions of the doctrine among members of their respective groups throughout the 20th century. Around the world, there are millions of adherents of the serpent seed doctrine