“And Adam knew Eve his wife; and she conceived, and bore Cain, and said, I have gotten a man from the LORD.”
In this verse the first husband and wife become the first father and mother. This new relationship must have been deeply interesting to both, especially so to the mother.
In naming her first born, Cain, or “acquired,” it is clear Eve believed he was the Seed promised to her in Genesis 3:15, the Promised One, the Messiah.
The problem here was that Cane was born of the seed of man. The promise of Genesis 3:15 would not be fulfilled until One was born of the seed of a women. And that One would be Jesus Christ.
The Truth
"But when the fullness of the time was come, God sent forth his Son, made of a woman, made under the law,” (Galatians 4:4)