The term "covenant" is of Latin origin (con venire), meaning a coming together. It presupposes two or more parties who come together to make a contract, agreeing on promises, stipulations, privileges, and responsibilities. In religious and theological circles there has not been agreement on precisely what is to be understood by the biblical term. It is used variously in biblical contexts. In political situations, it can be translated treaty; in a social setting, it means a lifelong friendship agreement; or it can refer to a marriage.

The biblical words most often translated "covenant" are berit [tyir.B] in the Old Testament (appearing about 280 times) and diatheke [diaqhvkh] in the New Testament (at least 33 times). The origin of the Old Testament word has been debated; some have said it comes from a custom of eating together (Genesis 26:30; 31:54); others have emphasized the idea of cutting an animal (an animal was cut in half [Genesis 15:18]); still others have seen the ideas of perceiving or determining as root concepts.

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The New Testament word for covenant has usually been translated as covenant, but testimony and testament have also been used. This Greek word basically means to order or dispose for oneself or another. The though of the inequality of the parties is latent.

The generally accepted idea of binding or establishing a bond between two parties is supported by the use of the term berit [tyir.B].

-- Gerard Van Groningen

For example:

Scholars have learned by studying tablets found by archaeologists that legal treaties between kings (suzerains) and subjects (vassals) existed during the time of the biblical patriarchs, Moses, Joshua, the judges, and the first kings of Israel. These treaties were written on tablets for the purpose of establishing a continuing relationship as determined and authorized by the suzerain. Once written, the covenants were not to be altered or annulled although parts could be explicated or elaborated. Did biblical writers borrow the idea of the covenant and its integral elements from pagan sources when the Old Testament was written — elements such as a self-presentation of the suzerain and his activities, including those done on behalf of the vassals, statements of intent, stipulations, and assurances of well-being if obedient and of curses if disobedient? The legal covenants included provisions for continuity, with emphasis on the suzerain's claim to vassals' children, and were confirmed by an oath or a special ratification ceremony, like the cutting in half of an ox or cow or the sharing of a meal as the conclusion of the act of covenanting.

These nonbiblical covenants were intended to serve a number of purposes, two of which are especially important to understand. The suzerain stated that as victor and lord over the vassals he had spared them in battle, delivered them from extenuating circumstances, and placed them in situations of life and well-being. This was an undeserved favor. The suzerain's covenant was also intended to serve an administrative function. It informed the vassals how the king would govern them and what they were to do in obedient response to him. These two purposes, the reminder of deliverance and the information on administration of affairs in daily life, appear in Yahweh God's covenanting with his people but in radically different ways.

Covenants, neither suzerain-vassal nor biblical, were not made (nor did they function) in a vacuum. Covenants presupposed a king, a domain, a way of life, people, and often mediating servants. The covenant was an important administrative means within a kingdom.

-- Gerard Van Groningen

Suzerain-vassal treaties (as seen among the Hittite kings) were made between a conquering king and the conquered. There was no negotiation between the parties.

1. The first element of these covenants is the preamble, which lists the respective parties. Exodus 20:2 begins with “I am the Lord your God.” God is the suzerain; the people of Israel are the vassals.
2. The second element is the historical prologue. This section lists what the suzerain (or Lord) has done to deserve loyalty, such as bringing the Hebrews out of slavery in Egypt. In theological terms, this is the section of grace.
3. In the next section, the Lord lists what He will require of those He rules. In Exodus 20, these are the Ten Commandments. Each of the commandments were considered morally binding on the entire covenant community.

-- Reformation Study Bible of Ligonier Ministries

When a covenant was made, it was often inaugurated and ratified by a blood sacrifice, as was the Abrahamic Covenant (Genesis 15:7-15), the Old Covenant (the Mosaic Covenant; Exodus 24:4-8), and the covenant that the leaders of Israel made to release their slaves (Jeremiah 34:8, 18-19).

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The shedding of blood was so central to the making of a covenant that the phrase “cut a covenant” was used of making covenants even when it seemed apparent that actual blood was not shed because the covenant was made with salt or in some other way. Unfortunately, this is difficult to see in most English Bibles because although the Hebrew text usually says “cut a covenant,” most English Bibles translate the phrase as “made a covenant” (cp. 1 Samuel 20:16; 2 Samuel 3:12, 5:3; 2 Kings 11:4; 2 Chronicles 29:10; Ezra 10:3; Psalms 89:3; Isaiah 57:8).

An animal was killed to ratify a blood covenant, but why? It was because the death of the animal represented the consequences of breaking the covenant. In killing the animals both parties were making a pledge that is known as a “self-maledictory oath” (an oath in which a person speaks potential harm to themselves). Thus, in killing the animals and walking between the pieces it was understood that if one of the parties broke the covenant they would be put to death like the sacrificed animals. The sacrificed animals showed the seriousness of the covenant and pictorially stated, “If I do not keep this covenant, may what happened to these animals happen to me.” Thus, if one party broke the covenant, that party would be subject to death.

Covenants were serious institutions, they were not “just words.” If a person made a covenant and broke it, that person was subject to death, something that has played out in blood feuds in the Middle East for millennia, and we see it in the Bible. For example, when the leaders of Israel made a blood covenant before God and then broke it, the leaders who made the covenant were the subject of divine retribution and death. God said, “I will even give them into the hand of their enemies… and their dead bodies will be for food to the birds of the heavens and to the animals of the earth” (Jeremiah 34:8-10,15-20).

-- REV commentary of Spirit & Truth Fellowship International

Our God comes; He does not keep silence;
before Him is a devouring fire, around him a mighty tempest.
He calls to the heavens above and to the earth, that he may judge his people:

“Gather to me my faithful ones, who made a covenant with me by sacrifice!”

The heavens declare his righteousness, for God himself is judge!

-- Psalm 50:3-6 (ESV)

God had made the following covenants with men:

I deliberately left out the Adamic Command because technically it was not a "covenant".

Testimony

Stephen said that God kept His promises (covenants) with Abraham, Moses, David and Isaiah until "the Righteous One" was murdered by the Jews.

And Stephen said:

“Brothers and fathers, hear me. The God of glory appeared to our father Abraham when he was in Mesopotamia, before he lived in Haran, and said to him, ‘Go out from your land and from your kindred and go into the land that I will show you.’

Then he went out from the land of the Chaldeans and lived in Haran. And after his father died, God removed him from there into this land in which you are now living. Yet he gave him no inheritance in it, not even a foot's length, but promised to give it to him as a possession and to his offspring after him, though he had no child.

And God spoke to this effect: that his offspring would be sojourners in a land belonging to others, who would enslave them and afflict them four hundred years. ‘But I will judge the nation that they serve,’ said God, ‘and after that they shall come out and worship me in this place.’

And He gave him the covenant of circumcision.

And so Abraham became the father of Isaac, and circumcised him on the eighth day, and Isaac became the father of Jacob, and Jacob of the twelve patriarchs.

“And the patriarchs, jealous of Joseph, sold him into Egypt; but God was with him and rescued him out of all his afflictions and gave him favor and wisdom before Pharaoh, king of Egypt, who made him ruler over Egypt and over all his household. Now there came a famine throughout all Egypt and Canaan, and great affliction, and our fathers could find no food. But when Jacob heard that there was grain in Egypt, he sent out our fathers on their first visit. And on the second visit Joseph made himself known to his brothers, and Joseph's family became known to Pharaoh. And Joseph sent and summoned Jacob his father and all his kindred, seventy-five persons in all. And Jacob went down into Egypt, and he died, he and our fathers, and they were carried back to Shechem and laid in the tomb that Abraham had bought for a sum of silver from the sons of Hamor in Shechem.

“But as the time of the promise drew near, which God had granted to Abraham, the people increased and multiplied in Egypt until there arose over Egypt another king who did not know Joseph. He dealt shrewdly with our race and forced our fathers to expose their infants, so that they would not be kept alive. At this time Moses was born; and he was beautiful in God's sight. And he was brought up for three months in his father's house, and when he was exposed, Pharaoh's daughter adopted him and brought him up as her own son. And Moses was instructed in all the wisdom of the Egyptians, and he was mighty in his words and deeds.

“When he was forty years old, it came into his heart to visit his brothers, the children of Israel. And seeing one of them being wronged, he defended the oppressed man and avenged him by striking down the Egyptian. He supposed that his brothers would understand that God was giving them salvation by his hand, but they did not understand. And on the following day he appeared to them as they were quarreling and tried to reconcile them, saying, ‘Men, you are brothers. Why do you wrong each other?’ But the man who was wronging his neighbor thrust him aside, saying, ‘Who made you a ruler and a judge over us? Do you want to kill me as you killed the Egyptian yesterday?’ At this retort Moses fled and became an exile in the land of Midian, where he became the father of two sons.

“Now when forty years had passed, an angel appeared to him in the wilderness of Mount Sinai, in a flame of fire in a bush. When Moses saw it, he was amazed at the sight, and as he drew near to look, there came the voice of the Lord: ‘I am the God of your fathers, the God of Abraham and of Isaac and of Jacob.’ And Moses trembled and did not dare to look. Then the Lord said to him, ‘Take off the sandals from your feet, for the place where you are standing is holy ground. I have surely seen the affliction of my people who are in Egypt, and have heard their groaning, and I have come down to deliver them. And now come, I will send you to Egypt.’

“This Moses, whom they rejected, saying, ‘Who made you a ruler and a judge?’
This man God sent as both ruler and redeemer by the hand of the angel who appeared to him in the bush.
This man led them out, performing wonders and signs in Egypt and at the Red Sea and in the wilderness for forty years.
This is the Moses who said to the Israelites, ‘God will raise up for you a prophet like me from your brothers.’
This is the one who was in the congregation in the wilderness with the angel who spoke to him at Mount Sinai, and with our fathers.
He received living oracles to give to us.

Our fathers refused to obey him, but thrust him aside, and in their hearts they turned to Egypt, saying to Aaron, ‘Make for us gods who will go before us. As for this Moses who led us out from the land of Egypt, we do not know what has become of him.’ And they made a calf in those days, and offered a sacrifice to the idol and were rejoicing in the works of their hands.

But God turned away and gave them over to worship the host of heaven, as it is written in the book of the prophets:

‘Did you bring to Me slain beasts and sacrifices,
during the forty years in the wilderness, O house of Israel?
You took up the tent of Moloch
and the star of your god Rephan,
the images that you made to worship;
and I will send you into exile beyond Babylon.’

-- Amos 5:25

Our fathers had the tent of witness in the wilderness, just as he who spoke to Moses directed him to make it, according to the pattern that he had seen.
Our fathers in turn brought it in with Joshua when they dispossessed the nations that God drove out before our fathers.

So it was until the days of David, who found favor in the sight of God and asked to find a dwelling place for the God of Jacob.

But it was Solomon who built a house for him.

Yet the Most High does not dwell in houses made by hands, as the prophet says,

"Heaven is my throne, and the earth is my footstool." "What kind of house will you build for me", says the Lord, or
"what is the place of my rest?" "Did not my hand make all these things?"

-- Isaiah 66:1-2

You stiff-necked people, uncircumcised in heart and ears, you always resist the Holy Spirit.

As your fathers did, so do you. Which of the prophets did your fathers not persecute?

And they killed those who announced beforehand the coming of the Righteous One, whom you have now betrayed and murdered, you who received the law as delivered by angels and did not keep it.”

-- Acts 7:2-53 (ESV)