We are grateful to Everett Fahy who recognised that this panel is by Stefano d'Antonio Vanni, a documented a collaborator of Bicci di Lorenzo. As he notes, there are many points of comparison with Vanni's frescoes of the Crucifixion in the church of Sant' Agostino, Volterra, and the ex-convent of San Girolamo alla Costa, Florence. Stefano's position in Bicci's studio was later filled by Neri di Bicci, and their styles bear some degree of resemblance. We are also grateful to Professor Miklós Boskovits, who has proposed an alternative attribution to Bicci di Lorenzo himself, suggesting that the panel is a late work, probably of the 1540s.
Sonia Chiodo has pointed out that the coat-of-arms on the reverse belongs to the Guidalotti family. The arms of this family were discovered under the Rinuccini arms in the Rinuccini chapel, in the Church of Santa Croce in Florence; it seems likely that the Guidalotti were the actual commissioners of Giovanni da Milano's (active c. 1346-1369) frescoes.