God has always demanded the co-operation of His people,
which is what a covenant is all about.
No need AT ALL for ANY of the many covenants,
IF man does NOT have a part to play!
So, you have never heard of a unilateral covenant?
Here, I will explain it to you. A "covenant" is a contract or formal agreement to do something. It can be unilateral or bilateral. A unilateral covenant is like the drawing up of a "will" or "testament" where the person has virtually no constraint on what they decide, and
the other party or parties have no say at all.
Now study up on the Abrahamic Covenant.
Then study up on the Covenant of Grace.
" . . . in the covenant of grace, that is, in the gospel, which is the proclamation of the covenant of grace, there are
no demands and no conditions. For
God gives what He demands;
Christ has finished all and has merited regeneration, faith and conversion for us; and the Holy Spirit applies them. But the covenant of grace does assume the form of a demand and a condition, to acknowledge man in his rational and moral nature, also to deal with him, although fallen, as created after God’s image, in order that also upon this highest plane, . . . he may be rendered responsible and inexcusable and enable him, consciously and freely, to enter into the covenant and break with sin.
The covenant of grace is; therefore, surely unilateral, it proceeds from God; He has planned and established it. He maintains and realizes it; it is a work of God Triune and completed, finished among the three Persons mutually." H. Bavinck, “
Gereformeerde Dogmatiek,” volume III, page 225.