King's first book, Newman and the Alexandrian Fathers: Shaping Doctrine in Nineteenth-Century England, published by Oxford University Press, was awarded a John Templeton Award for Theological Promise in 2011. His second book is a co-edited volume called Receptions of Newman. He is currently writing a book about the Oxford Movement's view of the laity, as well as co-editing The Oxford Handbook of John Henry Newman, both by Oxford University Press. He has lectured internationally on Newman and the Oxford Movement.