As I read what Luke records in 3.21-22, it reminds me of my baptism. Perhaps it does the same for you. Matthew tells us that this event took place and Jesus was baptized not for the remission of sins (beign himself sinless) but rather to fulfill all righteousness. And indeed when I (or any of us) went to the baptistry, there was the same purpose behind. In need of forgiveness, yes, and to fulfill the righteous requirements of the Lord. Further, the text says that God was pleased with His Son. And when we are obeedient to his commands, we too can be pleasing in His sight.
Luke emphasizes something that the other writers do not: “as he was praying.” Jesus is praying as he goes to be baptized. This is important because as we make our way through Luke, we will see Luke address this topic again and again concerning the ministry and life of Jesus. He was totally dependent upon the Father during his life and ministry on earth. When Jesus did all this he was “about thrity years old,” an approximation on the part of Luke based, no doubt, on his research.
Now for what we have been waiting for: how do we reconcile what appears to be such a vast inconsistency in the genealogical record of Jesus. I like what one commetator wrote concerning this: “To all this (that is the genealogical problems and possible solutions) it must be added that we possess not a poverty but a plethora of possibilities. Therefore the lack of certainty due to incomplete information need not imply error to either genealogy.” There are three explanations that scholarship poses as the most possible explanation: (1) Matthew records Joseph’s genealogy and Luke Mary’s; (2) the legal line is traced in Matthew and the actual line in Luke; (3) there was a levirate (someone married their brother’s widow) marriage at one or more points in the line. Which opinion one takes as reality is not the point of the record; the point of the record is to show that Jesus came to earth. Perhaps Luke has also in mind to link Jesus to every man by going all the way back to Adam, the first man. That would certainly be in line with his emphasis on the universality of salvation (Jews and Gentiles). The main focus is to show Jesus came to earth, he was God incarnate and is the unique Son of God. Whether it is traced back through his genealogical record or spoken from heaven, Jesus is the unique Son of God.