If I were pastoring a church right now, I would strongly emphasize the fact that Advent is — and always has been — a fast. I would not go directly to the standard lectionary or even Year D texts (unless it would be to emphasize the call to baptism through the Lukan tradition) and carols, although many of the plaintive Advent hymns set in a minor key may be very appropriate.
For this Advent 1, and then again at Ash Wednesday, and perhaps when the Jewish fall feasts come around again, I would turn to Joel 2 in order to "sanctify a fast," and call the people to "return to the Lord."
Why? Notice the structure of Joel. After the description of the locust invasion in Joel 1, Joel 2 seems less focussed on locusts than on a subsequent, even ultimate, "day of the Lord." Yes, the locusts are mentioned later, but as a memory of a past loss that shall be more than compensated for. But one does not need a literal locust swarm to goad the imagination into drawing associations between this prophecy and the state of the world, not just the land of Israel, today.
Indeed, there is an invading army of sorts mentioned in Joel 2, before whom the earth is completely overrun. Sound familiar? The description of their unswerving movement is terrible, they are relentless; but the Lord still has the power and authority to call them off.
Joel 2:1-2a is a Call to Worship, worship expressed through fasting.
Joel 2:2b-11 is what? An alarm? A reveille? A dissonant prelude?
Joel 2:12-16 is yet another Call to Worship, or a Call to Confession, bearing within it the first words of hope, hope specifically in the merciful nature of God (2:13b-14).
But notice how Joel 2:17 reads like a liturgical directory for worship, with explicit rubrics: The priest/minister should stand here, do this, say this. Yes, I would do this. Let all the chapter be read up to this point, perhaps in different voices. Physical, in-person attendance should be strongly encouraged. The people should have assembled together with a clear invitation into the presence of the Lord as the sanctuary, the safe and holy space. Then, not at all with the aim of drama or "acting," the minister(s) should proceed to the middle of the main aisle or whatever point is midway between vestibule and chancel, and stand in the midst of the people. Stand there. Consider the plight of this people, their pastoral needs, their sufferings, their losses, their fears and worries and heartbreaks. Consider God's holiness and how far we, his people, have fallen short. Consider the suffering of Jesus Christ for us. Whatever and however long it takes to let your heart swell. It need not be a long protracted sobbing or weeping, still less a forced squeezing of tears that are not there; but if the dam bursts, so be it; either way, with racking sobs or a single tear, let your voice convey what is in your heart; let it be true. And then say what the Word tells you to say:
"Spare your people, O Lord, and do not make your heritage a mockery, a byword among the nations. Why should it be said among the peoples, 'Where is their God?'" (2:17)
I would say this three times, at least. Each minister should say it at least once, the people should speak it as well. Perhaps minister, then choir (or children), then people.
A period of silence follows, as the minister(s) proceed(s) to the chancel.
Let the next word, the first word to break the silence, be the very next word of the text: "Then ..."
Joel 2:18-27 should be read with great hope and joy, and "then" (again!) it should be announced that this great reprieve for the people of God is borne even within "the day of the Lord" itself. Yes, though this day was declared at the opening of the reading, it shall not proceed to the terrible signs that have long been associated with that terrible day (2:28-32), according to the New Testament (Acts 2, Romans 10, etc.), ... not without this reprieve!
The point is this: If we take seriously the structure of Joel 2 and allow it to set the liturgy according to its own directions, we will discover hope, restoration, reprieve, and relief at the very heart of this chapter, sandwiched between the alarm that calls us to a fast and the apocalyptic collapse of the created order. The similarity, between this hope and the image of Israel safe in the land of Goshen while Egypt is plunged into thick, palpable darkness, is unmistakable. But this reprieve is not programmed to fall from the sky automatically. We are liturgically directed here to ask for it.
Let the remainder of the service unfold as the Spirit leads, with higher or lower liturgical elements. Some additional penitential elements might well be drawn and adapted from Return to God. Perhaps the times call for a series on the Ten Commandments, and Return to God has Prayers of Confession written in response to each of them. Perhaps on one such occasion, like Ash Wednesday, The Secret of Salix Babylonicus (which began life as a narrative sermon) might serve to interpret the Word. It is a parable that — quite apart from anything I had to do with it — gains greater relevance with each passing day. But my aim is not to push the books, it is simply and solely to equip the saints. Only do not let your flock languish or despair under the impression that God has appointed these days for unrelenting gloom. Not at all. That God desires to, and even gives us the very words with which to ask him to, relent — there is great, immense, and profound hope in this. It is a hope that has been encoded in the prophecy of Joel for well over 2000 years and undoubtedly encoded with a view to these very days.