The Preexistent Son: Recovering the Christologies of Matthew, Mark, and Luke," and argues that there are three sayings in the Synoptics that relate particularly to the coming of Jesus in regards to his pre-existent nature as God.
First, Jesus has two occasions where he faces demons and they ask if he "has come" to destroy them (cf. Matt. 8:29; Mark 1:24; 5:7; Luke 8:28). This presupposes that Jesus existed beforehand with authority as God.
Second, Jesus has six sayings where he declares why he "has come" into the world: to preach the gospel of kingdom, to call sinners to repentance, to fulfill the law and prophets, to cast judgement, to bring a sword, and to bring division among families (cf. Matt. 5:17; 9:13; 10:34-35; Luke 12:49). These reasons are all rooted in the activity of God in the OT (cf. Josh. 5:13-14; 1 Chron. 21:16), especially Luke 12:49 when Jesus says he will cast fire down on earth (cf. Gen. 19:24; Ex. 9:23; 2 Kings 1:10-12).
Third, Jesus uses the same theological title two times to articulate why he "has come" as Son of Man (Matt. 20:28; Luke 19:10). All of these "I have come" sayings according to Schreiner mean, "The purpose of Jesus' coming, implying that Jesus comes from outside the human sphere for a mission upon earth, which in turns suggests that his origin hails from outside the sphere of humanity." The Son of Man references are directly linked to Daniel 7 and suggest Jesus is like the "Ancient of Days" who is indeed God. All of these "I have come" statements are found in the OT by angelic visitors to God's people as well (cf. Dan. 9:22-23; 10:12, 14, 20). Therefore, they all point to Jesus Christ as the co-equal of the Father and display his pre-existence.
In Matthew 23:34-36, Jesus' pre-existence as the Son of God is fully disclosed. Jesus says he has sent the prophets just as God did in the OT. The OT clearly teaches God sent the prophets to his people. Gathercole notes for Jesus to say that "he sends the prophets" absolutely aligns him with Yahweh rather than with other human beings [prophets & wisdom teachers]. Schreiner mentions that there is no biblical or extra-biblical literature that mentions a prophet or wisdom teacher that claims such deity (i.e. pre-existence). This is pretty good internal evidence to support that Jesus is the pre-existent Son of God!