No one knows for certain which bishop saint stands beside Saint Francis in this small, luminous panel by Fra Angelico, painted around 1420—an enigma that has sparked debate among art historians for decades. Some suggest the figure may be Saint Louis of Toulouse, others lean toward Saint Nicholas or Saint Augustine, but the lack of clear attributes leaves the question open. This uncertainty is not unusual for early works by Fra Angelico, whose career began in the vibrant artistic circles of early Renaissance Florence, where saints and their stories were painted to inspire devotion and wonder. At the heart of the painting, Fra Angelico captures a moment of quiet reverence: Saint Francis, robed in simple brown, displays the stigmata on his hands, a sign of his mystical union with Christ's suffering.

The bishop saint, dressed in a richly patterned cope and mitre, gestures in blessing or perhaps in recognition of Francis's sanctity. Gold leaf shimmers behind them, separating the holy figures from the earthly realm and drawing the eye to their serene faces. The delicate, almost miniature scale of the figures recalls the intimate devotional panels of Masolino, yet Angelico’s gentle modeling and luminous color already hint at the spiritual clarity that would define his later work. The origins of Saint Francis and a Bishop Saint are not fully documented, but it likely formed part of a predella or a small altarpiece, intended for private devotion or a monastic setting.

Its early date places it among the first known works by Fra Angelico, painted before his celebrated frescoes at San Marco. Over the centuries, the panel has passed through the hands of collectors and institutions, its attribution shifting as scholarship advanced. Today, it stands in the Museo del Prado, a testament to the early flowering of Renaissance art and the enduring mystery of its unnamed saint.