When Joseph discovers that Mary is pregnant, he decides to divorce her privately rather than have her publicly stoned to death for adultery. But then he changes his mind after a most mysterious dream. Tt is true that Mary has been chosen, that is, favored by God. Mary is to be blessed by having a child out of wedlock who would later be executed as a criminal. But today's gospel portrays blessedness quite differently.
Blessedness begins with humiliation.
Humiliation then gives rise to gratitude, and finally to faith. Faith that is produced by the avoidance of humiliation is not faith at all, but triumphalism. Whom the Lord would bless, he first abases. Faith is not some easy, onward and upward flight from struggle. Faith is forged on the anvil of adversity.