Definition and Overview:
In biblical theology, a covenant is a solemn agreement or promise between God and His people, often accompanied by specific conditions and obligations. The concept of covenant is central to the narrative of the Bible, serving as a framework for understanding God's relationship with humanity. Covenants in the Bible are characterized by divine promises, human responsibilities, and often a sign or seal to confirm the agreement.

Major Biblical Covenants:

1. The Noahic Covenant:
After the flood, God established a covenant with Noah and all living creatures, promising never to destroy the earth with a flood again. The sign of this covenant is the rainbow. The conditions were primarily on God's part, with the expectation that humanity would respect life and justice. Genesis 9:11-13 states, "I establish My covenant with you: Never again will all life be cut off by the waters of a flood; never again will there be a flood to destroy the earth. And God said, 'This is the sign of the covenant I am making between Me and you and every living creature with you, a covenant for all generations to come: I have set My rainbow in the clouds, and it will be a sign of the covenant between Me and the earth.'"

2. The Abrahamic Covenant:
God's covenant with Abraham included promises of land, descendants, and blessing. The conditions required Abraham to walk before God and be blameless. The sign of this covenant was circumcision. Genesis 17:1-2 records, "When Abram was ninety-nine years old, the LORD appeared to him and said, 'I am God Almighty; walk before Me and be blameless. I will establish My covenant between Me and you, and I will multiply you exceedingly.'"

3. The Mosaic Covenant:
Given at Mount Sinai, this covenant established Israel as God's chosen people, with the Law (Torah) as its foundation. The conditions were obedience to the Law, which included moral, ceremonial, and civil regulations. Exodus 19:5-6 states, "Now if you will indeed obey My voice and keep My covenant, you will be My treasured possession out of all the nations—for the whole earth is Mine. And unto Me you shall be a kingdom of priests and a holy nation."

4. The Davidic Covenant:
God's promise to David ensured that his lineage would endure forever, culminating in the Messiah. The conditions were less explicit, focusing on God's faithfulness to David's house. 2 Samuel 7:12-16 highlights, "When your days are fulfilled and you rest with your fathers, I will raise up your offspring after you, who will come from your own body, and I will establish his kingdom. He will build a house for My Name, and I will establish the throne of his kingdom forever."

5. The New Covenant:
Prophesied in Jeremiah and fulfilled in Jesus Christ, the New Covenant offers forgiveness of sins and a transformed heart through the Holy Spirit. The conditions involve faith in Jesus Christ and acceptance of His sacrifice. Jeremiah 31:33 declares, "But this is the covenant I will make with the house of Israel after those days, declares the LORD. I will put My law in their minds and inscribe it on their hearts. And I will be their God, and they will be My people."

Theological Significance:
Covenants in the Bible reveal God's initiative in establishing a relationship with humanity, highlighting His faithfulness and grace. They also underscore human responsibility to respond in faith and obedience. Each covenant builds upon the previous, culminating in the New Covenant, which fulfills and transcends the earlier covenants through the life, death, and resurrection of Jesus Christ. The conditions of the covenants emphasize the importance of holiness, trust, and commitment to God's will, reflecting the moral and spiritual order God desires for His people.