Almost simultaneously with his works for the Orsanmichele, between 1415 and 1426 Donatello produced five statues for the campanile of the Cathedral of Santa Maria del Fiore in Florence. These set of statues of Prophets constitutes the most important work of Donatello’s youth and are currently deposited in the Museo dell’Opera del Duomo. They include the sculptures of the Beardless Prophet (also known as “Prophet with a Scroll”) and the Bearded Prophet (both from between 1418-1420); the Sacrifice of Isaac (ca. 1418); Habbakuk (also known as Lo Zuccone, 1423-1426); and Jeremiah (1423–1426). Donatello’s vision of a “Prophet” was all valid in biblical terms, religiously significant and figuratively stimulating. In effect, Donatello’s model of a “Prophet” represented not only a man predestined by God to become “His voice” during certain moments in the history of Israel, but also represented a man of his time who participated with his particular personality in the history of his people for which he was individually and physically committed. In this sense, Donatello’s placed his prophets in the infinity of times, and at the same time in their own time. From this artistic concept derived the new demand for an individual expression, we would almost say, a necessity of an imaginary “portrait”. Thus, in his Bearded Prophet, we can envision the sadness of ancient pessimism, of the “Vanity of Vanities” described in Ecclesiastes. This is also evident in the figure of Jeremiah, his expression of contempt (almost of rejection) of the idolatrous mobs, impregnates his old body. In these figures of his Apostles, Donatello almost reflected the types of the ancient Classical portraiture, especially those from the end of the Republic and from the beginning of the Empire. For Donatello, the Roman portraiture represented an inexhaustible repertoire of human types and anatomical details, which also he saw were reflected in the contemporary men that surrounded him. The fundamental difference was that, in the Roman portrait, the man appeared representing a documentary effigy, almost balanced with his vital aspects; instead, in Donatello’s images, he wanted to reflect the mark the anguish of life and the search for faith had left on their faces as time went by. In these Prophets, we can see a spontaneous and univocal will to participate in life and history.
From ca. between 1425-1430 is the Pazzi Madonna relief in the Bode-Museum in Berlin, and from ca. 1408-1409 comes the notable Crucifix for Santa Croce. In this work, Donatello portrayed Christ in a moment of agony, with his eyes and mouth partially opened, and his body contracted in an ungraceful posture. Between 1422 to 1428, Donatello collaborated with Michelozzo to produce the funerary monument of the Antipope John XXIII for the Baptistery in Florence focusing on the recumbent bronze figure of the deceased placed under a lunette. In 1427, he finished a marble relief for the funerary monument of Cardinal Rainaldo Brancacci for the church of Sant’Angelo a Nilo in Naples, and by the same period, he executed the relief of the Feast of Herod and the statues of Faith and Hope for the Baptistery of San Giovanni in Siena. The relief showing scenes of the Feast of Herod (1423-1427) represents Donatello’s first great example of low relief where we can appreciate an extremely effective perspective, from the representation of the architectural forms among which the scene unfolds (three successive atriums with arches and pilasters in a late-Roman style) placed among figures of a provocative voluptuousness, down to the type of thick and dense relief of the figures in the foreground that, little by little, end up being resolved in the faint figures of the background. From the low relief of the tabernacle of Saint George onward, Donatello committed to the exclusive use of the schiacciato technique in his reliefs and reaching higher levels of mastery and accuracy in its use, which allowed him not only to emulate real perspective in a reduced space, but to emulate plasticity and movement. In order to achieve this, Donatello made the profile lines to stand out with greater clarity, as seen in the mentioned Madonna Pazzi relief of the Berlin Museum and in the Assumption of the Virgin of the Brancacci Monument, in Naples. In the Madonna Pazzi, the Classical purity is evident in Donatello’s modeling (almost emulating the work of Phidias for the frieze of the Parthenon). Also notable are the vitality of the new composition, and the sweet naturalness observed in the placement of the Child inside the living space determined by the figure of his Mother, thus determining a semi-elliptical layout that will remain engraved for a long time on the eyes of the artists of the Renaissance.