[Jesus] portrays His Gospel [in Matthew chapter 22] in beautiful, lovely tones, comparing it to a wedding, not a time for work or sadness, but a time for festivity and joy, when people dress themselves specially, sing, play, strike up the music, dance, feast, drink, and are happy all around and in good spirits. It would be no wedding, certainly, just to work, be sad, or mourn. Christ, accordingly, describes His Christendom and the Gospel in terms of earth’s happiest occasion, namely, a wedding. And by this He teaches us that His Gospel is a proclamation of love and joy, a truly joyous wedding celebration where Christ is the bridegroom and the Christian church, the bride, and our mother. Beautifully, magnificently the Lord portrays the kingdom of heaven, that is, His kingdom on earth, or the Gospel, as a wedding, in order winsomely to urge and coax us to come to Him in His kingdom, to accept His Gospel. We are to bear in mind, that it is to the wedding we want to go; it will be beautiful and delightful; we will be truly happy, our hearts and spirits lifted up in song. In this way our Lord seeks to urge us to regard the Holy Gospel as the choicest of treasures and greatest joy on earth.
Martin Luther, Third House Postil for the Twentieth Sunday after Trinity (Matthew 22:1-14)