Irenaeus Against Heresies, Volume 4

3. And teaching this very thing, He said to the Jews: "Your father Abraham rejoiced that he should see my day; and he saw it, and was glad"(5) What is intended? "Abraham believed God, and it was imputed unto him for righteousness."(6) In the first place, [he believed] that He was the maker of heaven and earth, the only God; and in the next place, that He would make his seed as the stars of heaven. This is what is meant by Paul, [when he says, ] "as lights in the world."(7) Righteously, therefore, having left his earthly kindred, he followed the Word of God, walking as a pilgrim with the Word, that he might [afterwards] have his abode with the Word.