In 2013-2014 he was the William E. Simon research fellow in the James Madison Program at Princeton University and a visiting scholar at Princeton Seminary. He has published seven books including The Declaration of Independence and God (2015) and The Natural Moral Law (2013) with Cambridge University Press. His areas of research include epistemology, the ethics of belief, intellectual history, and religious pluralism. He regularly teaches Philosophy of Religion, Introduction to Philosophy, Applied Ethics, World Religions, Western Religious Traditions, and Religion in America.