If the baptism was the opportunity for the Father to express his delight in Jesus, and the occasion of the Spirit’s equipping Jesus for his work, then as far as Jesus was concerned it was an act of dedication to his work. Now the time had come, and with eagerness he presses forward to the task. His whole heart and mind and body were committed to working out the salvation of sinners.
Luke tells us that as his baptism happens Jesus is praying. Now we know that Jesus was a man of prayer, therefore it is not surprising that he was praying. Luke is the Gospel writer who draws attention to the fact that Jesus prayed, and Luke highlights this aspect of Jesus at crucial events in his public ministry: he spent a whole night in prayer before he called his disciples (6:12); he prayed at the feeding of the 5,000 (9:16); when his disciples confessed he was the Son of God, it was after he had been praying (9:18); his purpose in going up the hill on which the transfiguration took place was to pray (9:28); it was as Jesus was praying that his disciples asked to be taught to pray (11:1); he prayed in Gethsemane (22:40, 46); he prayed for the soldiers at Calvary (23:34); he prayed in the house in Emmaus (24:30).
His baptism was also his first public identification with sinners. John had found Jesus’ request for baptism to be puzzling, after all John’s baptism was for those who confessed sins and repented of them. But Jesus over-ruled John and in baptism linked himself with sinners.
But his baptism by John also revealed that Jesus was committing himself to save not only Jews but Gentiles. It has been discovered that baptism with water was a ritual whereby Gentiles were admitted to Judaism. So while Jews too were submitting to the baptism it was a clear sign that Jesus was stepping across Jewish barriers to save Gentiles.