Christians around the world mark the beginning of Lent today with the celebration of Ash Wednesday. This ancient day and season has a surprising modern appeal. Priests and pastors often tell you that outside of Christmas, more people show up to church on Ash Wednesday than any other day of the year—including Easter. But this mystique isn’t reserved for Christians alone. The customs that surround the season have a quality to them that transcend religion.

Perhaps most notable is the act of fasting. While Catholics fast on Ash Wednesday and on Fridays during the Lenten season, many people—religious or not—take up this increasingly popular discipline during the year.

But Pope Francis has asked us to reconsider the heart of this activity this Lenten season. According to Francis, fasting must never become superficial. He often quotes the early Christian mystic John Chrysostom who said: “No act of virtue can be great…