What was Abraham's role in the covenant promise he received?
Abraham was merely the subject of the covenant promise, not its mediator, author, or guarantor. The promise was spiritual and heavenly in origin, and he could not touch, change, or enforce it. God alone initiated, mediated, and fulfilled the covenant, keeping it settled even when Abraham's offspring repeatedly broke it.
Les explains that the covenant promise made to Abraham was entirely spiritual and heavenly in origin. It never left the hands of spiritual beings, and as it was given to Abraham, that's all it was. Abraham merely became the subject of it; he couldn't touch it, he couldn't change it. Even though his offspring would break it repeatedly, God kept it settled and never went back on it. Les also points out that a mediator is normally a go-between in a controversy, but God is not using a three-person mediation. God is the mediator, the instigator, and the fulfiller, and He alone is involved. Therefore, the covenant's certainty rests on God, not Abraham.