John Calvin Commentary Genesis 5:2

"male and female created he them, and blessed them, and called their name Adam, in the day when they were created." — Genesis 5:2 (ASV)

Male and female created he them. This clause commends the sacred bond of marriage and the inseparable union of husband and wife. For when Moses mentioned only one, he immediately afterwards includes both under one name. And He assigns a common name indiscriminately to both, so that future generations might learn to cherish this connection with each other more sacredly, when they saw that their first parents were called one person.

The trivial inference of Jewish writers, that married persons only are called Adam (or man), is refuted by the history of the creation. Nor, truly, did the Spirit in this place mean anything other than that after the establishment of marriage, husband and wife were like one man.

Moreover, He records the blessing pronounced upon them, so that we may observe in it the wonderful kindness of God in continuing to grant it; yet let us also recognize that by the depravity and wickedness of humankind it was, to some degree, interrupted.