One needs to understand the way God made a covenant with Abraham to understand. Abraham was present, but was put into a deep sleep during the covenant process, allowing God to make the covenant himself and with no commitment on Abraham's part. Abraham cant take credit for accepting the covenant any more then we can take credit for accepting salvation.
Without God drawing us in the first place, there would be no ability to respond.
God works in us to will and to do according to His good pleasure.