Robert Letham, presbyterian pastor and theologian, teaches Systematic Theology at the Wales Evangelical School of Theology, formerly Evangelical Theological College of Wales. Previously he was Senior Minister of Emmanuel Orthodox Presbyterian Church Wilmington Delaware for 17 years. He has taught at London Bible College (now London School of Theology), and most recently was Adjunct Professor of Systematic Theology at Westminster Theological Seminary Philadelphia and Visiting Professor of Theology at Reformed Theological Seminary, Baltimore / Washington DC.