This essay explores J. I. Packer’s theological influence through a con- sideration of his many writings. It classifies his input into six strands: Luther, Calvin, and the Puritans; Scripture; Anglicanism; universalism, revivals, and the Holy Spirit; Christ’s work; and the book Knowing God. This survey reveals that Packer used his exceptional theological mind to educate both Anglicans and other types of Protestants.