3. in process of time--Hebrew, "at the end of days," probably on the Sabbath.
      brought . . . an offering unto the Lord--Both manifested, by the very act of offering, their faith in the being of God and in His claims to their reverence and worship; and had the kind of offering been left to themselves, what more natural than that the one should bring "of the fruits of the ground," and that the other should bring "of the firstlings of his flock and the fat thereof" [Ge 4:4].

JFB.