And now your two sons, Ephraim and Manasseh, who were born unto you in the land of Egypt before I came unto you into Egypt, are mine; as Reuben and Simeon, they shall be mine.
All Commentaries on Genesis 48:5 Go To Genesis 48
Hippolytus of Rome
AD 235
This clearly shows [that Jacob makes Ephraim and Manasseh his own]. Since Jacob had twelve sons, to whom the twelve tribes owed their existence, he distributed the two sons of Joseph into two tribes; and so the tribes became thirteen as the tribe of Joseph was divided between his two sons. And therefore Paul himself, the apostle, was related to these events. After being chosen among the tribes, he was counted the thirteenth after the apostles, and so he was sent to the Gentiles as apostle.