Romans 4:16
Therefore it is of faith, that it might be by grace; to the end the promise might be sure to all the seed; not to that only which is of the law, but to that also which is of the faith of Abraham; who is the father of us all, Therefore it is of faith, that it might be by grace; to the end the promise might be sure to all the seed; not to that only which is of the law, but to that also which is of the faith of Abraham; who is the father of us all,
Abraham is the father of us all as the father of the faithful. His faith was proved when he accepted in his heart the command to offer his son, enduring the test as completely as if he had himself taken his son's life. Through faith human beings receive the divine nature and overcome, as set forth in Romans 4 and 5. This is possible because Christ has joined humanity with divinity, so that by faith humanity can lay hold upon the divine nature.