David M. VanDrunen (Ph.D., Loyola University Chicago; J.D., Northwestern University) is Robert B. Strimple Professor of Systematic Theology and Christian Ethics at Westminster Seminary California. A minister of the Orthodox Presbyterian Church and an attorney, his books include Natural Law and the Two Kingdoms: A Study in the Development of Reformed Social Thought (Eerdmans, 2010), and Bioethics and the Christian Life: A Guide to Making Difficult Decisions (Crossway, 2009).