Lewis was born on 8 June 1953.[3] He was educated at King Edward VI School, Southampton[4] and Merton College, Oxford, where he read Oriental Studies (Hebrew, Aramaic, and Syriac)[5] taking a BA in 1974 and MA in 1979. He was formed for the priesthood at Cuddesdon Theological College, taking his second Oxford degree in the Final Honour School of Theology in 1977.[3]