Irenaeus of Lyons · a new plain-English translation from the original language
That Abraham beheld Christ; that the faith he held and the faith we hold are a single, identical faith. Teaching this very point, He told the Jews: Abraham your father exulted at the hope of seeing my day; he beheld it, and rejoiced. What then does this mean? Abraham trusted God, and this was credited to him as righteousness — first, because He is heaven and earth's Fashioner, the sole God; and second, because He would render his offspring as numerous as heaven's stars. This is what Paul means by: as lights within the world. Rightly, then, setting aside every earthly attachment, he followed after the Word of God, traveling in the Word's company that he might come to dwell with the Word. Rightly too the Apostles, drawing their lineage from Abraham, abandoned boat and father to follow the Word of God. Rightly too we ourselves, having taken up the very faith Abraham held, and bearing the cross just as Isaac bore the timber, follow after Him. For in Abraham humankind had already been trained and made ready beforehand to follow the Word of God. Indeed Abraham, obeying the Word of God's command through his faith, willingly surrendered his cherished only son as an offering to God, so that God in turn might be pleased, on account of Abraham's entire posterity, to give up His own cherished and only-begotten Son as an offering for our deliverance.
Abraham, being at that time a prophet, and perceiving by the Spirit the coming day of the Lord and the design of His suffering — through which he himself, together with all who trust God as he trusted, would begin to attain salvation — rejoiced beyond measure. The Lord, then, whose day he yearned to behold, was no stranger to Abraham; nor was the Lord's Father a stranger to him, for he had come to know Him through the Lord's own Word and had put his trust in Him. For this cause it was credited to him as righteousness by the Lord. For it is faith set upon God that makes a man righteous; and for this cause he declared: I will reach out my hand toward the God Most High, founder of heaven and earth. Yet those holding wicked opinions labor to overturn all of this because of a single saying, one which, in truth, they have grasped poorly.