When I wrote Covenant Relationships about 25 years ago, I had in mind both the Great Commandment and the Great Commission.
The Great Commandment tells us to love God and to love one another (Leviticus 19:18, Deuteronomy 6:5, Luke 10:27). Loving God may be a little easier because He is perfect. The problem with loving people is that they are not.
If we are to love real people with real problems, we must have some framework and guiding principles. The framework is the covenant; the principles are two-fold: loyalty and integrity.
The Great Commission includes sharing the gospel to the ends of the earth (Acts 1:8), praying for a worldwide revival (Acts 2:17), and restoring all things since creation (Acts 3:21). Those tasks are too big for anyone. There is only one way to proceed: we must work as a team.
To work as a team in cooperation, we must again have a framework and guiding principles. The framework is covenant; the principles are loyalty and integrity.

Without the Cross – This won’t work

The problem is that it doesn’t work! Even with covenant, loyalty and integrity, our relationships are doomed to failure. Why? – Because we human beings are still selfish and sinful. We need something else to help us. This is where the cross comes in.
There is a conflict between loyalty and integrity. Everyone we try to be loyal to lacks integrity somewhere. There is a gap between the desire to remain faithful to that person and the fact that the person lacks integrity (to some degree). How can I show loyalty to someone who is lacking integrity?
We need grace. In order to stay faithful to people who are not perfect, we must choose the cross; we must choose sacrificial love; we must choose to grant grace when the other fails. Our grace toward other people must fill in the gap when they fail. We must take their failures and weaknesses upon ourselves. That is painful. That demands faith.
Covenantal principles alone are not enough; they must be filled up with a cross-like attitude, with the love of Yeshua who died on the cross for us when we failed. He showed loyalty to us when we did not act in integrity. We have to act that way to others, and they will have to act that way to us. That’s the only way covenantal relationships can succeed.