We must go to the Bible to understand just how important a Covenant can be. The Bible records exactly what God meant by the word, so it is vital to read the scriptures given in this article.
A Covenant is basically a binding agreement, binding for life usually, but if God is a party, that means usually the Covenant is everlasting and perpetual. To be instituted, the Covenant usually entails the shedding of blood and the sacrifice of an animal or person--that means, it is a matter of life and death.
God detailed specifically what was required of the parties involved, Himself and the People of Israel, and what blessings they obtained by being faithful to the stipulations of the Covenant, and also warned of the curses or penalties they would incur if they proved unfaithful.
Why should we study Covenants? Are they applicable to Gentile Christians? We believe the Covenants, especially the everlasting ones, are very important to Gentile Christians, and yet we who are Gentiles are largely ignorant of them and their significance. Some churches and pastors may teach on Covenants, but many do not. Generations have passed since society generally understood Biblical Covenants. America's Founders understood Covenants, and the Declaration of Independence and the Constitution are modeled on Biblical Covenants and the very structure of the Israelite nation and its division of powers and other institutions. Middle Eastern societies and cultures still retain a certain knowledge of Covenants, but that cannot be said of Western industrialized societies.
If we do not understand Covenants (though we have a certain knowledge of business contracts), we cannot understand a "Covenant God" either. As Christians we read a compilation of sixty-six holy scriptures called the "Bible"--a term deriving from the pagan Phoenician port of Byblos where the paper was produced that was made into books--and the names given to its two sections are "Old Testament" and "New Testament," but the word "testament" is more properly "Covenant," since that is meant. As it is, we get a legal view expressed in the word "testament," that is superficial and does not do justice to God's Covenantal nature and Covenant-love, which a bare legal term does not describe adequately. This point should become clearer as the article continues.
There exist a number of critical and foundational covenants still in force, though most of us Christians are only barely aware of that fact, or only superficially appreciate what that means.
1. Genesis 9:15: God's Covenant with Noah and Descendants and every living thing on earth. Token or sign of this Covenant is the Bow in the clouds (popularly called the "rainbow," though that is a misleading name for God's Covenant Sign, since it has no spiritual significance attached to rain, and the Bow is not merely a decorative feature (beautiful as it is) but may signify the war bow of an archer, in this case, God being the Divine Archer dispensing peace and mercy by laying down his Bow of enmity against the earth). This Covenant is perpetual, or everlasting. As God states, the earth need never fear again total destruction by water.
2. Genesis 15:18: God's Covenant with Abraham and Posterity. Token or sign: circumcision of males, Gen. 19:10. This Covenant is perpetual or everlasting.
3. Exodus 2:24: God's Covenant with Isaac and descendants. This Covenant is perpetual or everlasting.
4. Exodus 2:24: God's Covenant with Jacob and Posterity. This Covenant is perpetual or everlasting.
5. Deut. 29:1: God's Covenant with the people of Israel at Horeb. This Covenant is perpetual or everlasting, so their Posterity is included.
6. Psalm 89: God's Covenant with David and his Posterity. Token or Sign: The Moon. Note: This Covenant is absolute in criticality, for it entails the Royal Messianic Line of Christ and its preservation, not merely David's descendants being preserved so that they may sit on the throne of Israel or Judah.
7. Isaiah 42:6: God's giving of the people of Israel for a Covenant of the People, for a light to the Gentiles. The Covenant entails the blessing Israel will be to all the nations. It is everlasting in duration.
8. Jeremiah 31:31, 31:33: A New Covenant. God covenants with His people, instituting a New Covenant that will be written in their hearts. It is everlasting.
9. Exekiel 34:25: Covenant of Peace.
10. Malachi 2:4: God's Covenant with Levi.