Ganssle serves with the Rivendell Institute for Christian Thought and Learning, a special project of the Campus Crusade for Christ student ministry at Yale University. He has taught philosophy at Syracuse University and has worked as a teaching fellow and part-time lecturer in the philosophy department at Yale University. He has published academic papers on God's relation to time, free will, and St. Augustine. He has also coedited an anthology of philosophical essays for Oxford University Press called God and Time: Essays on the Divine Nature.