One of the first things we learn about Covenant is that it is not strictly speaking a contract. It has elements that are contractual in nature, but it has one significant difference–it is not null and void if we default. God does not foreclose because the Covenant is a relationship, not a regulation.
The phrase for this is “steadfast love” (hesed), and it runs across the pages of the Old Testament, becoming agapé in the New Testament. Unfortunately, one of the biggest misinterpretations of Scripture is the allegation that the Old Testament is about Law, and the New Testament is about Love. No, no, no–it is Love all the way through: hesed/agapé from cover to cover! This is seen in Deuteronomy 6:4 and Leviticus 19:18, the two passages Jesus combined to show the essence of the Covenant and of the Christian life (Matthew 22:34-40).
Walter Brueggeman has repeatedly pointed this out in his writings, that the Torah was a love document, not a law code. . After the fall in Genesis 3, it was the way God sought to turn things around and stop the downward spiral created by the originating sin of egotism/ethnocentrism. God initiated the redemption.
The Covenant is, of course, based in mutual commitment. The phrase, “I will be your God, and you will be my people” shows this. And when mutual commitment is in place, life works the way God intended–just as it did in the Garden of Eden before the Fall. Mutual commitment via the Covenant is a “new Eden,” not located in one place, but wherever God and humankind live together in love.
With respect to the practice of the better it means we do not act as we do to appease an angry God or to avoid foreclosure, but as our response to grace. It is not about “pay back” but about what people call “paying it forward”–as Jesus put it, “Freely you have received, freely give” (Matthew 10:8). The practice of the better means we consider it a privilege to care for others in keeping with the ways God has cared for us.
 Walter Brueggemann, ‘Disruptive Grace’ (Fortress Press, 2011. He speaks to this more than once, particularly in the section about “Torah.”