Israelites of the Old Testament era made their promises usually in the forms of covenants, oaths and vows. They therefore understood the promises of God in relation to such forms (Exod 6:8; Deut 9:5; Eph 2:12; Heb 6:13; see COVENANT; OATHS; VOWS). In the New Testament, although the idea of the covenant is present, there is little concerning oaths and vows. Usually the emphasis is on the promise, and most of the promises are made by God (2 Cor 1:20; Titus 1:2). Some of these promises are in the nature of fulfilled prophecies, where God’s promises of Old Testament times find their fulfilment in the events of Christ and the gospel (Luke 1:32-33,72-73; Acts 13:23,32; Rom 1:2; 15:8; Gal 3:14; Heb 9:15; cf. Gen 12:1-3; 2 Sam 7:16; Jer 31:31-34). Others concern the gift of the Holy Spirit to the church (Luke 24:49; Acts 1:4; 2:33,39), and the blessings of the believer in the age to come (Heb 10:36; James 1:12; 2:5; 2 Peter 3:4,13; 1 John 2:25). The New Testament therefore refers to the entire gospel and its blessings as being based on promise.
That is, salvation is God’s gift, dependent on God’s faithfulness and in no way a reward for human effort or merit (Gal 3:18; 4:23-28; 2 Tim 1:1; Heb 4:1; 10:36). God’s promises are contrasted with the law given to Israel; for whereas the law demanded obedience, the promises require only faith to accept them (Rom 4:13-16; Gal 3:17-18; 3:21-22; Eph 3:6; Heb 8:6; 11:13). God is always faithful to his promises. He has given added assurance of this by giving the Holy Spirit to the believer as a guarantee that he will do what he has promised (Eph 1:13-14; Heb 6:13; 10:23; 2 Peter 3:9). God’s people likewise should be faithful to their promises, even when it involves them in personal inconvenience (Deut 23:23; Ps 15:4; 2 Cor 1:17-20).