If you pay attention to the story of Christmas, Joseph seems fairly insignificant, if not altogether unimportant. To me, at least, he seemed like a necessary character to tell the story of Christmas; but the real focus is on the birth of Christ.
If you read the gospel accounts, Joseph never says a word. And the “main” characters are Mary (of course, being the mother of God) and Jesus (being the incarnate son of God).
However, Frederick Dale Bruner, commentator on Matthew, sees Joseph as having a significant role in the account, especially considering the later teaching of Jesus.
In the NT Joseph never speaks. In Matthew’s gospel, where Joseph appears more than anywhere else, he does a number of important things. In the first chapter he overcomes the initial hesitation and obeys the divine summons to marry a questionable Mary; in the second chapter he is commanded to flee to Egypt with child and his mother; still later in that chapter, counseled again by a dream, he is instructed to return with the family to the land of Israel and then to settle with them in the north of Galilee. In every scene Joseph simply acts without speaking. His speech is to do the will of God.
We may call him “Quiet Joseph”. His hallmark is obedience — prompt, simple, and unspectacular obedience. And in this sense Joseph prefigures one important feature in this gospel’s understanding of righteousness: to be righteous is simply to obey the Word of God; righteousness is just to do (a favorite word in the this gospel) what God says… The unostentatiousness of Joseph’s obedience here prefigures Jesus’ later description of righteousness’s unique way (in the heart of the Sermon on the Mount, chap. 6) of not seeking to be noticed by people. Righteousness, in Matthew, is — simply obeying. The “more” that Jesus requires for entrance into the kingdom (5:20) turns out, in some cases in the gospel (as now with Joseph), to involve a simply “less” of show. In Jesus’ teaching it is sometimes the devout Serious who are “too much”. Thus, Joseph, the divinely chosen adopting father of Jesus, lives out for us in his noiseless way an exemplary preliminary definition of righteousness in the gospel.
Matthew presents Joseph as the picturesque righteousness required for the kingdom. In this way, Joseph actually prefigures the greater, “quiet righteousness” of Christ. Christ quietly obeyed the will of his Father. And his righteousness was for the redemption of his people.