Despite his admiration for Donatello as one of the finest sculptors of his age, the Florentine artist best known as Filarete cautioned readers of his Trattato dellarchitettura: "If you have to do apostles, do not make them look like fencers, as Donatello did in the bronze doors in the sacristy of San Lorenzo in Florence" (Spencer v.2, Bk. XXIII, [f.179.sup.v]). Filarete's remark echoed a similar injunction in Alberti's renowned De Pictura that an artist should not represent a discoursing philosopher in a manner more suited to a fencer (Grayson 74; Spencer 124). Both contemporary admonitions noted Donatello's rendering of figures in the midst of extreme movement on the bronze doors, while drawing attention to the problematic subject of Donatello's bronze reliefs. At the same time, these criticisms recommend a context in which that subject might be located and understood: Donatello's commission at San Lorenzo coincided with the rediscovery of Quintilian's Institutio Oratoria. Newly available to the avant-garde of Florentine humanists, the Institutio Oratoria lent ancient authority to the role of physical movement and gesture for conveying meaning during speech-making. Correspondences between Quintilian's text, with its remarkably precise discussion of oratorical delivery, and Donatello's gesticulating figures suggest that the recovery of this manuscript allowed Donatello to cast his Christian preachers as ancient orators, thus placing the eloquence of classical oratory at the service of Christian piety.
The 1980s restoration of Donatello's decorations in the Old Sacristy brought renewed attention to the function of this space as both sacristy and Medici memorial sepulchre (fig. 1). Donatello's extraordinary use of color, as well as his working methods in reviving the use of stucco as a relief medium for the first time since antiquity, could be newly appreciated. The celestial hemisphere, frescoed in the cupolina above the altar, proved to be of greater complexity and significance than previously imagined. Nevertheless, the Medici-commissioned bronze doors still constituted one of the most significant aspects of the decorative scheme, as Donatello's contemporaries recognized.
Bronze was an expensive material in quattrocento Florence, and the unique enterprise of figurated bronze door-making is highlighted by the scarcity of earlier Italian precedents. (1) While the concomitant surge of interest in such doors is attested by the increased demand for them, Donatello's sacristy doors were one of the few examples brought to fruition. They also remain the only set of bronze doors commissioned by private patrons during this period. In lieu of primary documentation concerning the chronology of Donatello's commission or working procedures, the doors have been bracketed between Cosimo de' Medici's return from exile in 1434, and Donatello's departure for Padua in 1442.
Given other notable contemporaneous bronze door making (and planning) in Florence and Siena, Donatello would have recognized the prestigious nature of a commission that demanded such substantial investment of his time and attention. Donatello surely labored under the impetus to excellence set by the example of Ghiberti's first set of bronze doors, whose overall arrangement of two narrative units in five registers for a total of ten panels...