While at North Carolina State, Frei heard a lecture by the prominent theologian H. Richard Niebuhr, began corresponding with him, and eventually enrolled for a Bachelor of Divinity degree at Yale Divinity School (YDS), Niebuhr's base.
Frei was present for a talk given by prominent theologian H. Richard Niebuhr at North Carolina State; they began communicating, and Frei later pursued a Bachelor of Divinity degree at Yale Divinity School (YDS), which was Niebuhr’s institution.