Looking death in the face, Joseph rallies for one final act of faith in Genesis 50. He recalls God’s promise to Abram (Gen. 15:13, 14) and assures his brethren that God will bring them out of Egypt and back to the Promised Land. He commands them to “carry up my bones from hence,” binding them with an oath. Accordingly, Moses takes the bones of Joseph with him when Israel goes out of Egypt (Ex. 13:19).

Why was Joseph sure that God would keep His promises? It was because he knew the promises were stipulations of God’s covenant with Abraham, sealed with God’s oath, “two immutable things, in which it was impossible for God to lie” (Heb. 6:18). God had spoken. That was enough for Joseph.

The notion of covenant is older than the Bible and embedded in the culture of the ancient Near East. The human authors of Scripture use the word without expla­nation or elaboration for their readers. The basic mean­ing of the Hebrew word berith is “agreement.” The Greek word diatheke means “arrangement,” such as a will, the legal instrument by which one disposes of earthly goods and property after death. The two words have in common the binding character of what is “agreed” or “arranged” (Gal. 3:15). Promises must be kept and obligations must be per­formed, no matter what.

God’s covenants are “agreements” between Himself and His people, defining their relationship to Him. There are two parts: first, what God promises to do for them, and second, what they are obliged to do in response. Many cov­enants are recorded in Scripture: the covenant of works implicit in the history of Adam and Eve, and their life in Eden as regulated by God’s commandments (Gen. 1, 2); the creation covenant with Noah after the destruction of the old world by the flood (Gen. 9); the covenant with Israel enacted at Sinai (Ex. 19, 20); and the covenant with David and his house (2 Sam. 7).

These covenants are overshadowed by the covenant of grace made with Abraham (Gen. 17:7), confirmed and renewed as “the new covenant” in Christ’s blood (Jer. 31:31-34; Matt. 26:28) and proclaimed as “the promise” by Peter at Pentecost (Acts 2:39). The other covenants are applications of the covenant of grace to particular people or to their special needs or circumstances. Some continue to bind God and man (the covenant of works, the creation covenant with Noah), but others have been fulfilled in Christ (the covenants with Israel and the house of David) and are no longer binding.

Justified by faith in Christ, Christians are the blessed seed of “faithful Abraham” (Gen. 15:6; Rom. 4:11-12; Gal. 3:7-9). Together with their children, they are bound to God as His people, and He has bound Himself to them as their God (Gen. 17:7; Acts 2:39). The children of believers, how­ever, are not saved by the covenant relationship automati­cally; rather, they must personally be brought to repentance and faith in the Lord Jesus Christ. By God’s grace, and through saving faith, they are heirs to all that God has promised them in Christ; they are obliged, for Christ’s sake, to cleave to this one God, trusting in Him and loving Him with all their hearts, forsaking the world, crucifying the old nature, and walking in newness and holiness of life.

The New Testament gives much attention to the develop­ment and varying emphases between the old covenant made with Israel at Sinai through Moses and the new covenant established in Christ in fulfillment of the promises made to Abraham. The epistle to the Hebrews expounds this development at length, showing the superiority of Christ and His “new covenant” to anything given to Israel through Moses.

Noting this difference, some have argued that the moral law, summarized in the Ten Commandments (Ex. 20, Deut. 5), as part of the Mosaic covenant, is not binding on Chris­tians under the gospel. But long before Moses, the moral law was written in the human heart (Rom. 2:14). Sin was imputed and punished by death, from Adam to Moses (Rom. 5:13-14). Christ Himself declared that He did not come to destroy the law (Matt. 5:17). As a rule of life for believers, the moral law is an essential part of the covenant of grace.