For those who joyfully recognize in Jesus the bridegroom of the covenanted people, the deprivation of fasting is out of the question. Celebration is the only meaningful response. And yet Jesus himself hints that the wedding will be delayed while he is taken away from them, and then they will mourn longingly for him. He anticipates the irony of Israel’s indifferent and even hostile rejection of the wedding invitation. But they will not succeed in spoiling the celebration. In fact, the wideness of God’s mercy will throw the invitation open to the nations, bringing in the bad along with the good, so that the wedding hall is filled with guests.
But even for them, a note of warning is sounded. Those who do accept the king’s invitation must still be properly attired for the occasion or suffer painful expulsion. And finally, the imminent return of the bridegroom requires of God’s people watchful attention to their personal readiness. Some will be unprepared and disqualified; others will be waiting in alertness and therefore received into the marriage feast, after which the door will shut.
– Ray Ortlund. God’s Unfaithful Wife: A Biblical Theology of Spiritual Adultery. New Studies in Biblical Theology series, volume 2. InterVarsity Press, 1996. pp. 138-139.