Let us suppose I hire a painter to paint a house I own out in the country. I sign a contract in which I agree to pay for travel expenses an amount up-front, and a final amount upon conclusion. We travel to the site and discover the property has burned down. True to the contract, I pay for travel and up-front expenses, but that is all. The house being burned down means the contract cannot be fulfilled. I terminate the contract without fault and the painter and I go our separate ways.
Now let us suppose the same situation, but we have a covenant to paint the house. Together, we rebuild it, as the covenant places a moral and spiritual obligation to see to it that a painted house results from our efforts. The money for the job is not as important as the job. We do not go our separate ways, because we have a covenant that implies we maintain and watch over that house.
This is why I do not have a contract with God. I have a covenant. The covenant is to return my soul to Him, and I labor with Him in that effort.