Jon at The Theological Ramblings of an Anglican Ordinand has linked to a lecture give by Simon Gathercole in Jesus’ “I have come” sayings in the Synoptic Gospels (Part 1 | Part 2 | Part 3). I’ve embedded the audio files for all of you Firefox/Safari/Chrome (?) users. For those reading this in a feed the player might not display so just use the links above.
I personally think that Gathercole makes a persuasive case and would recommend his book The Preexistent Son: Recovering the Christologies of Matthew, Mark, and Luke to anyone interested in the subject. For dissenting views see James Dunn’s review in RBL as well as chapter 6, “Jesus as Messiah and Son of God in the Synoptic Gospels,” in Adela Yarbro Collins’ recent King and Messiah as Son of God: Divine, Human, and Angelic Messianic Figures in Biblical and Related Literature. Aquila H. I. Lee also interacts with some of Gathercole’s earlier work on the subject in his published dissertation From Messiah to Preexistent Son: Jesus’ Self Consciousness and Early Christian Exegesis of Messianic Psalms.