Matthew 1:2

The omission of the names of Ishmael and Esau is explained by the fact, that they were not only not in the line of succession, but were outside the covenant with Abraham — “In Isaac shall thy seed be called” (Genesis 21:12); and Esau had forfeited both the birth-right and the blessing. The brethren of Judah are named, on the other hand, because all who were descended from them had an equal interest in the Messiah.