Place in the Antediluvian Line
According to Genesis 5:9-14, Cainan was born when his father Enos was ninety years old. He fathered Mahalaleel at the age of seventy, afterward had further sons and daughters, and lived a total of nine hundred and ten years. Through his son Mahalaleel the line continued to Jared, Enoch, Methuselah, Lamech, and Noah.
He thus stands in the fourth generation from Adam by way of Seth, within the line that Scripture sets apart from the descendants of Cain. The genealogy is the whole of what the biblical text preserves concerning him: his parentage, the age at which he became a father, that he had other children, and the length of his life.
In the Genealogy of Christ
Cainan is also named in the genealogy of Jesus given in the Gospel of Luke, which traces the ancestry of Christ back through Noah and the antediluvian patriarchs to Adam (Luke 3:36-37). His inclusion there places him among the ancestors of Christ according to the flesh.
It is in this capacity that the Orthodox Church remembers him. Together with the other forefathers from Adam through Joseph, he is commemorated as one of the righteous of the Old Testament whose lineage and faith preceded and pointed toward the Incarnation.
Commemoration
Cainan has no individual biography in the Orthodox synaxarion; he is honored corporately among the Holy Forefathers rather than for any recorded deeds of his own. His commemoration falls on the Sunday of the Holy Forefathers, the second Sunday before the Nativity of Christ, on which the Church celebrates the patriarchs, prophets, kings, and righteous ancestors who lived before and under the Law.
The liturgical texts of that Sunday present these forefathers as having been justified by faith and as having prepared, through their descent, the way for Christ's coming. Cainan is numbered among the antediluvian patriarchs of the line of Seth who are recalled in this commemoration.
