[The] covenant of grace was first revealed in the promise of the Savior that God gave to Adam and Eve (Gen. 3:15). It was more fully expressed in the promises God made to Abraham and his seed (Gen. 17:7). Finally, it was renewed, confirmed, and enlarged by the shedding of Christ’s blood at Calvary (Matt. 26:28; 2 Cor. 1:20). As in all the covenants God makes with human beings in Scripture, the covenant of grace is extended to believers and their children (Acts 2:39).

Joel R. Beeke, Parenting by God’s Promises, xvi.