The Promise of God to Abram, The Mosaic Covenant and the New Covenant in Christ | Genesis Bible Study

 The promise God made to Abram, the Mosaic Covenant, and the New Covenant in Christ are connected, but they are not the same covenant. Each was established at a different time, with different participants, signs, purposes, and obligations.

1. God’s covenant promise to Abram

God first called Abram in Genesis 12, long before the Law of Moses was given.

“I will make of thee a great nation, and I will bless thee, and make thy name great… and in thee shall all families of the earth be blessed.”
—Genesis 12:2–3, KJV

God’s promises to Abram included:

• A promised land

• A multiplied seed or descendants

• The formation of a great nation

• Kings coming from his lineage

• A covenant relationship with his descendants

• Blessing reaching all the families and nations of the earth

In Genesis 15, God formally confirmed the covenant. Abram divided the animals, but God alone—represented by the smoking furnace and burning lamp—passed between the pieces.

“In the same day the LORD made a covenant with Abram.”
—Genesis 15:18

This is important: God placed the covenant’s fulfillment upon His own faithfulness. Abram believed God, and his faith was counted to him for righteousness:

“And he believed in the LORD; and he counted it to him for righteousness.”
—Genesis 15:6

Circumcision was later given as the sign of this covenant in Genesis 17. It did not originate the promise; it outwardly marked those belonging to the covenant family.

2. The Mosaic Covenant

The Mosaic Covenant was established approximately four centuries later, after God delivered Israel from Egypt. It was made with the nation of Israel at Mount Sinai through Moses.

“Now therefore, if ye will obey my voice indeed, and keep my covenant, then ye shall be a peculiar treasure unto me.”
—Exodus 19:5

This covenant included:

• The Ten Commandments

• Civil judgments governing Israel

• Priestly and ceremonial ordinances

• Sacrifices

• Dietary and purity laws

• The tabernacle and Levitical priesthood

• Blessings for obedience

• National judgments for disobedience

Unlike the promise to Abram, the Mosaic arrangement repeatedly used conditional language: “If ye will obey.” It regulated Israel’s life as a covenant nation and revealed God’s holiness, human sinfulness, and the need for atonement.

The Mosaic Law did not cancel the earlier promise to Abraham.

“The covenant, that was confirmed before of God in Christ, the law, which was four hundred and thirty years after, cannot disannul.”
—Galatians 3:17

Paul’s point is decisive: the Law came later and therefore could not erase or replace God’s promise to Abraham.

The Law served as a tutor or guardian pointing people toward Christ:

“Wherefore the law was our schoolmaster to bring us unto Christ, that we might be justified by faith.”
—Galatians 3:24

The Mosaic Covenant exposed sin, governed Israel, and prepared the way for the Messiah. It was never the basis upon which God originally gave Abraham the promise.

3. The New Covenant in Christ

The New Covenant was promised by the prophets and established through the blood, death, and resurrection of Jesus Christ.

“Behold, the days come, saith the LORD, that I will make a new covenant with the house of Israel, and with the house of Judah.”
—Jeremiah 31:31

Its provisions include:

• God’s law written upon the heart

• An inward knowledge of God

• Complete forgiveness of sins

• The gift and indwelling of the Holy Spirit

• Spiritual renewal

• Access to God through Christ

• One redeemed covenant people composed of believing Jews and Gentiles

At the Last Supper, Jesus declared:

“This cup is the new testament in my blood, which is shed for you.”
—Luke 22:20

The word translated “testament” also means “covenant.” Therefore, it may properly be understood as “the New Covenant in My blood.”

The sacrifices of the Mosaic system could not permanently remove sin. They repeatedly pointed forward to the one sufficient sacrifice of Christ.

“For by one offering he hath perfected for ever them that are sanctified.”
—Hebrews 10:14

The essential distinctions

How the three relate

The three should not be blended together, but neither should they be completely separated.

flowchart TD
    A["Promise to Abraham"] --> B["Seed, land and blessing"]
    B --> C["Mosaic Covenant with Israel"]
    C --> D["Law exposes sin and points forward"]
    B --> E["Jesus Christ—the promised Seed"]
    D --> E
    E --> F["New Covenant in Christ's blood"]
    F --> G["Forgiveness, Spirit and worldwide blessing"]

The movement of Scripture is:

1. God promised blessing through Abraham and his Seed.

2. God formed Israel into a covenant nation through Moses.

3. The Mosaic Law revealed sin and prepared Israel for the Messiah.

4. Christ came as the promised Seed of Abraham.

5. Christ established the New Covenant through His blood.

6. Through faith in Christ, believing Gentiles participate in Abraham’s spiritual blessing.

“And if ye be Christ’s, then are ye Abraham’s seed, and heirs according to the promise.”
—Galatians 3:29

This does not mean that Gentile believers become Abraham’s physical descendants or that every national and territorial promise loses its original meaning. It means they are joined to Christ—the promised Seed—and receive the blessing of justification, the Spirit, and covenant fellowship with God through Him.

The clearest distinction

The Abrahamic promise says, in effect: God will provide the Seed through whom the nations will be blessed.

The Mosaic Covenant says: God’s redeemed nation must live under His holy commandments, and the Law exposes its need for atonement.

The New Covenant says: The promised Seed has come; through His blood, God grants forgiveness, writes His law upon the heart, and gives the Holy Spirit.

Therefore, Christ did not create an unrelated promise, nor did the Mosaic Law replace Abraham’s covenant. Jesus fulfilled the redemptive purpose toward which both the promise and the Law were pointing.