Eusebius of Caesarea

See how distinctly he alludes to this [Mosaic] covenant when he says God did not give the same covenant to their fathers [Abraham and Noah]. For if he had said that absolutely no covenant was given to their fathers it would have been a false statement. For Holy Scripture testifies that a covenant of some kind was given both to Abraham and Noah. And so Moses adds that one “not the same” was given to their fathers. This points to that other greater and glorious covenant, by which all of these were shown forth as friends of God.