God has made a number of covenants we read about in Scripture. Contracts and covenants often are considered similar but they are not. Although there are similarities between a contract and a covenant they are not alike. A contract involves two parties agreeing to a set of conditions, but if one party fails to keep the contract it is no longer valid. It’s bilateral, conditional, revocable and dissoluble.

But a covenant is unilateral, unconditional, irrevocable and indissoluble. For example, if someone says, “I will keep my word and do what I said, whether you do or not,” it is unilateral, unconditional. This is the way God’s covenant’s function. A covenant is a one-sided agreement where one party promises to do certain things regardless of circumstances. A covenant can be specified without anything given in return.

The major covenants which are mentioned in the bible to teach mankind its own sinfulness and helplessness, and his or her need of God's power and grace.

The following verses are from the New International Version except where noted:

The first one was made with Noah, to preserve earth's living souls through the deluge.

Gen. 9:11 I establish my covenant with you: Never again will all life be destroyed by the waters of a flood; never again will there be a flood to destroy the earth.” 12 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:

Thereupon God said He would not to repeat the flood, and is signified by the rainbow.

Gen. 9:13. I have set my rainbow in the clouds, and it will be the sign of the covenant between me and the earth. 14 Whenever I bring clouds over the earth and the rainbow appears in the clouds, 15 I will remember my covenant between me and you and all living creatures of every kind. Never again will the waters become a flood to destroy all life. 16 Whenever the rainbow appears in the clouds, I will see it and remember the everlasting covenant between God and all living creatures of every kind on the earth.”

Another was with Abram when He and leased him the land.

Gen 15:18 On that day the Lord made a covenant with Abram and said, “To your descendants I give this land, from the Wadi of Egypt to the great river, the Euphrates—

He added to it, assuring him a seed, signified by circumcision.

Gen 17:10-11 This is my covenant with you and your descendants after you, the covenant you are to keep: Every male among you shall be circumcised. 11 You are to undergo circumcision, and it will be the sign of the covenant between me and you

Another major covenant was made with Israel in the wilderness, giving them the law, which they could not keep.

Duet. 4:13 He declared to you his covenant, the Ten Commandments, which he commanded you to follow and then wrote them on two stone tablets
2 Chron. 5:10 There was nothing in the ark except the two tablets that Moses had placed in it at Horeb, where the Lord made a covenant with the Israelites after they came out of Egypt.

He made a renewed covenant, a 'new' covenant with them, to be fulfilled in the millennium, in the presence of their Messiah.

Jer. 31:31-32 “The days are coming,” declares the Lord, “when I will make a new covenant with the people of Israel and with the people of Judah. 32 It will not be like the covenant I made with their ancestors when I took them by the hand to lead them out of Egypt, because they broke my covenant, though I was a husband to them,”

The final major one is our spiritual 'covenant,' today.

Heb. 9:15 For this reason Christ is the mediator of a new covenant, that those who are called may receive the promised eternal (eonian) inheritance—now that He has died as a ransom to set them free from the sins committed under the first covenant.

Heb 9:15 Rotherham version... And, for this cause, of a new covenant, is he mediator,—to the end that, death coming to pass for the redemption of the transgressions against the first covenant, the called might receive the promise of the age-abiding (eonian) inheritance;

And in other instances, specific covenants are mentioned distinct from the Sinai covenant. Some of these are:

Joshua 24:25 So Joshua made a covenant with the people that day and set them a statute and an ordinance in Shechem.

! Samuel 18:3 Then Jonathan and David made a covenant because he loved him as his own soul.

2 Kings 11:17 And Jehoiada made a covenant between the LORD and the king and the people, that they should be the LORD'S people; between the king also and the people

Psalm 89:3 I have made a covenant with my chosen, I have sworn unto David my servant,

Psalm 89:28 My mercy will I keep for him for evermore, and my covenant shall stand fast with him.

Also, sometimes it is used in a figurative sense, like:

Job_31:1 I made a covenant with mine eyes; why then should I think upon a maid?

The lesson all of this teaches is that: covenants or contracts made by men are too often broken, God alone is able to never break a covenant He makes. Glory to the unchangeable God Almighty.