Marius van Willigen: Was Ambrose’s Joseph-Christ typology of Genesis 37:13 already well-known in the fourth century?

In the interpretation of Genesis 37:13-14 Ambrose of Milan provides the reader with a typological exegesis: Jacob represents God the Father, Joseph is a typus Christi, who is visiting his brothers, the lost children of Israel. Although this exegesis seems peculiar, Ambrose presents the interpretation of this passage as a well-known one. This evokes different questions. First of all, as Jean Daniélou indicated in Sacramentum Futuri the early origin of Adam’s and Isaac’s typology, is the Ambrosian Joseph-typology comparable with the examples which Daniélou provided? Is the Ambrosian Joseph-typology of Gen. 37:13-14 therefore addible to these examples of Danielou and classifiable in a Genesis-canon of typologically explained patriarchs? Furthermore, is Isaac, as a patriarch and sacrifice, comparable with Joseph, the son of Jacob? And is it imaginable that Joseph, as a typologically interpreted patriarch, possessed a solid position in earlier Christian exegesis? The typological exegesis of Gen.37:13-14 is not only existent in the De Ioseph of Ambrose, as a representative of the Alexandrian exegetical school. The same typological exegesis of Joseph as the Son of God sent to his brothers is existent in the sermons of John Chrysostom too. Nevertheless Chrysostom is a representative of the Antiochene exegetical school. The Syrian writer Ephraem also chose for a typological exegesis of the same passage, an exegesis which anyway represents the heart of Christian belief.