Biblical morality is characterized by an indicative-imperative structure. That is, all of its imperatives (moral commands) are proceeded by and grounded in indicatives (statements of fact), either explicitly or implicitly. The most important indicative that grounds the imperatives in Scripture is that the recipients of Scripture are the covenant people, that is, members of the community of the covenant of grace. The Old Testament Scriptures were not given to the world at large but to the people of Israel, God’s covenant people of old. “He has revealed his word to Jacob, his laws and decrees to Israel. He has done this for no other nation; they do not know his laws” (Ps. 147:19-20). Neither were the New Testament Scriptures given to the world at large but to the church, the new covenant people. p. 39 David Van Drunen, A Biblical Case for Natural Law (Grand Rapids : Acton Institute, no date)
The atoning death of Christ, and that alone, has presented sinners as righteous in God’s sight; the Lord Jesus has paid the full penalty of their sins, and clothed them with His perfect righteousness before the judgment seat of God. But Christ has done for Christians even far more than that. He has given to them not only a new and right relation to God, but a new life in God’s presence for evermore. He has saved them from the power as well as from the guilt of sin. The New Testament does not end with the death of Christ; it does not end with the triumphant words of Jesus on the Cross, “It is finished.” The death was followed by the resurrection, and the resurrection like the death was for our sakes. Jesus rose from the dead into a new life of glory and power, and into that life He brings those for whom He died. The Christian, on the basis of Christ’s redeeming work, not only has died unto sin, but also lives unto God. Christianity & Liberalism by J. Gresham Machen, p. 114 book, p. 90 pdf below.