Le nouvel empereur Dèce interroge saint Laurent sur les trésors de Philippe et lui donne trois jours pour les trouver.

Mariotto di Nardo was a prominent Florentine altarpiece painter active from the late fourteenth into the mid-fifteenth century, bridging the generations from Orcagna to the early Renaissance. This scene — the Emperor Decius interrogating Saint Lawrence about the church's treasures — comes from a cycle dedicated to Saint Lawrence, deacon and martyr of the third century. Lawrence's famous reply to Decius (that the poor are the church's true treasure) made him a saint associated with charitable giving and was beloved by Florentine guilds and confraternities engaged in poor relief. The narrative scene, depicting confrontation rather than miracle, was a relatively uncommon choice.

Mariotto places the confrontation within an architectural setting of stylized arches and columns, establishing spatial recession through overlapping architectural planes rather than consistent perspective. The emperor's court is indicated by rich textiles — brocaded robes rendered with fine hatched lines — contrasting with Lawrence's simpler deacon's vestments. The palette retains the strong complementary contrasts of Trecento convention: deep reds against cold blues.