It has been proposed that this Crucifixion, like two panels also in The Frick Collection portraying an Augustinian monk and nun, originally formed a part of Piero’s S. Agostino altarpiece. The first known reference to The Crucifixion is found in a seventeenth-century document listing paintings in a collection at Borgo Sansepolcro. The Crucifixion is described there in considerable detail, together with three other subjects: a Flagellation, a Deposition, and a Resurrection, all three now lost. The writer did not claim that these panels came from the S. Agostino altarpiece, although in the same collection were four larger panels of standing saints that he specified did come from the high altar of S. Agostino. While he names only St. Michael and St. Augustine correctly, these larger panels may be identified with the four saints discussed in the entry on Piero’s St. John.
The seventeenth-century record does not, therefore, resolve the problem of whether or not The Crucifixion belonged to the same altarpiece. Piero did, after all, paint other works for his native town, which might have had predellas incorporating such scenes. The question of possible workshop participation in painting The Crucifixion is also an unresolved issue. Some scholars argue that an assistant was responsible for the execution, although certain passages of this small yet monumental composition are painted with great refinement.
Source: Art in The Frick Collection: Paintings, Sculpture, Decorative Arts, New York: Harry N. Abrams, 1996.