Leonard Goppelt, who wrote a dissertation on typology in the 1930s that became the foundation for the twentieth century's understanding of typology from a salvation-historical perspective, in his NT theology:
The typological understanding of the Old Testament was not an exegetical method but a distinctly defined angle of vision. . . . Looking back from the Christ event Paul observed in persons, institutions, or events of the Old Testament advance signals of God's activity in the end time. These types were not something like historical analogies. They were God's connections to the human being that were witnessed to by the Old Testament and that announced--positively or antithetically--a corresponding but at the same time eschatologically elevated, final connection. The announcement character rested on God's loyalty to his promise.
--Theology of the New Testament (Eerdmans 1982), 58
This was according to the eternal purpose that he has realized in Christ Jesus our Lord . . . --Ephesians 3:11