By the fourth century, the celebration of Christ’s mass, the birth of Jesus, had taken hold as a unique Christian festival on or around December 25. Scholars are unclear as to why this date: it could very well have been a reaction to, or an appropriation of, the pagan solstice festivals taking place at that time. As the non-Christian world heralded “the birth of the invincible sun,” our Christian forebears claimed the verse from Malachi 4:2, which promised that the “Sun of Righteousness will rise with healing in its wings.” More light, pouring forth into the gloom of the year.

As Christian theology developed, the larger mystery of the Incarnation—of God taking on human flesh—eventually became a touchstone for Christmas celebrations. Not only has God’s chosen One appeared among us, blazing like the sun, but this One is God himself, bound up in our human mess, taking on our human suffering, living and dying as one of us.

For some ancient Christians, the Incarnation itself is what saves us. The Cross and Resurrection are merely part of a larger whole. When a holy God touched a corrupt humanity, God’s goodness reversed our corruption, restored us to holiness. We were like a basket of rotten apples coming in contact with one good apple: not only did the good apple retain its essential goodness, but it reversed the decay of all the rest.

This is the good news of Christmas, the “good spell” or gospel, that brings healing—not only to each of us, but to a hurting world.

Sarah Arthur is an editor of literary guides to prayer from Paraclete Press, including Light Upon Light: A Literary Guide to Prayer for Advent, Christmas, and Epiphany, from which these devotions are adapted (©2014 by Sarah Arthur, used by permission). Her forthcoming book, with coauthor Erin Wasinger, is The Year of Small Things: Radical Faith for the Rest of Us (Brazos Press).