It is others in the Gospels that call him the 'Son of God', but also others also call him the 'Son of David', and Mary Magdalene, after he is "risen from the dead" and therefore supposedly in Spirit, calls him merely 'Teacher'.
Interestingly, Magdalene’s original confusion of his being the 'Gardener' points to a good interpretation of 'Son of Man' where we can assign 'Man' to Adam, the first man, (of Adam and Eve in the Garden of Eden; Adam, the first gardener); thus 'Son of Man' would mean merely a descendant of Adam. In other words, Jesus seems to be saying that he is a just a human, perhaps an implied perfect one, incidentally a Jewish uncircumcised one!
The question arises as to whether Jesus was just being modest, but Jesus does not appear to be afraid of proclaiming his greatness, as seen in his Trial:
'Caiaphas says to Jesus, "I adjure you, by the living God, that you may say to us, if you are the Christ, the Son of God. Jesus replies, "You have said that, not me; nevertheless I say to you, you shall see the Son of Man sitting on the right hand of the power, and coming upon the clouds, of the heaven.' (Matt 26:63,64)
This leaves us with the only possible conclusion that, if Jesus does not say that he is the 'Son of God', then he is not the 'Son of God'. Once this is realized and accepted, we can put away the major problem that Christianity has with the Jewish and Islamic faiths which is the insistence that if Jesus is the 'Son of God' then Christianity must be the only true religion.
Please listen to the YouTube song that I wrote:
Jesus never said he was the Son of God
In this music video the verses in the New Testament are shown in which others can him the 'Son of God'.
To give the real meaning of 'Son of Man' would be too extensive to cover here, but the brief synopsis is to state that Jesus is saying that he is third in position in the Church hierarchy of:
- the Pope acting for God,
- Gabriel (called an angel -- see the Annunciation at Luke 01:26 --as God's voice to Man, 'Man' for short), and
- Son of Man or Holy Spirit
These positions in the hierarchy of the Essene Qumran Community of the Dead Sea Scrolls, were:
- Simon Magus (Acts 8:9-11; raised by Jesus as Lazarus in John 12:1-53; as the naked youth at the Judas betrayal at Gethsemane in Mark 14,51,52; later excommunicated by Peter in Acts 5:1-6 as Ananias; then called '666' in Revelation),
- Jonathan Annas, the son of the High Priest Annas (called the disciple James of Alphaeus and also called 'Father' by Jesus in Gethsemane), and
- Jesus, the David King, the Christ
More details are at the Pesher of Christ website.
Later. it is clear that the Church apostles, under the direction of Jesus, (he having survived the Crucifixion) combined all three positions into this now mystical Jesus Christ.