In our three-year lectionary cycle, most Hebrew Bible texts come up once at most. Isaiah 58 is assigned five times. We justice-minded Christians tend to find additional reasons to turn to it as well.

Not all of them are good ones. There is a tendency to see in this text not only a fierce call to treat workers with dignity, share food with the hungry, and invite the homeless in, but also a general rejection of religious ritual. Often this is relatively benign: this matters more than that. But sometimes it involves a dismissive attitude toward Catholics, Orthodox, and high-church Protestants—toward the sort of Christians whose faith centers on a lot of doing that isn’t just doing justice. It can even take an anti-Jewish turn, alleging that the fasting and other religious practices of Isaiah’s original audience demonstrate that they had categorically missed the point of their own religion.

But the text doesn’t quite say that God cares about justice and not ritual. The prophet takes aim not at ritual generally but at empty, fraudulent ritual—at a ritual container devoid of content. Christians with limited positive experience of the faith’s more ritual-oriented traditions (I was one once) sometimes elide this distinction, perceiving ritual as empty by definition. But it isn’t—not in contemporary Christianity or Judaism, and certainly not in the religious imagination of the Hebrew Bible.

Ritual and justice are both major biblical themes, but they don’t exist in a push-pull relationship. They are integral to each other. This is perhaps clearest in the subject of the sabbath. Sabbath-keeping is a religious practice, commanded by God and passed down by tradition, and it is certainly ritualized: there are things one does and doesn’t do on the sabbath, many of them more symbolic of genuine rest than invested in it literally. But the sabbath also has deep ethical implications that are part and parcel to its ritual observance. Keeping the sabbath means providing for the rest needed by workers, by animals, by the land, by one’s self. It is irreducibly both ritual and ethical, both fast and justice.

Our reading from Isaiah 58 ends at verse 12. Verse 13 is about the sabbath: “If you refrain from trampling the sabbath, from pursuing your own interests on my holy day . . . then you shall take delight in the Lord.” That’s interests in the older sense of economic stakes, not hobbies. We honor God with genuine, ethically infused religious ritual, within which we seek to pursue God’s economic interests rather than our own.

Yet the temptation of empty ritual looms. It’s just so easy to go through the motions while ignoring faith’s deeper claims on us. “So much of human religiosity comes down to a hoax we try to perpetrate on God,” writes Shai Held, commenting on Isaiah 58 in these pages (Living by the Word, August 14, 2019). “We’ll give You worship, we say in effect, ​and You just mind Your own business. Your place is the church, the synagogue, or the mosque; butt out of our workplaces and our voting stations.”

But God isn’t having it, says Held. “If you want to worship me,​ God says, ​you’re going to have to learn to care about what I care about—and who.” God requires worship that embodies this care, and true worship in turn helps cultivate this care. Ritual and justice are mutually reinforcing.

Most Protestants don’t do much fasting anymore. I don’t know that misreadings of Isaiah 58 are to blame. Yet I wonder what it would be like if we embraced our Protestant bona fides and gave this text a doggedly literal reading. Yes, its ethical demands are intense. But at face value the text calls for us to do these things as a fast, as the fast that God chooses. Fasting is good! It’s also temporary, and perhaps we could muster the courage to take this sort of radical action if we knew it had an endpoint.

We could fast from affluenza, avoiding all spending beyond bare essentials. We could use the extra money to do more to help the poor than we ever thought we could afford. We could share food with every hungry person we meet; we could even invite someone who is homeless into our home. We could work to build a ritual practice infused with justice.

If we tried to commit at this level permanently, we might find it unsustainable. (I know I would.) But the short-term commitment of a fast might be more doable—yet still shape us for the better ethically. It might also give us a deeper respect for religious ritual and for those who practice it.