He painted so many pictures during this second residence at Fiesole, not only for public places, but for private citizens, that Vasari wrote: "This Father painted so many pictures, which are dispersed through the houses of the Florentines, that sometimes I am lost in wonder when I think how works so good and so many could, though in the course of many years, have been brought to perfection by one man alone."
In 1436 the great Cosimo de Medici insisted that the monks of Fiesole should again leave their convent, and remove to that of San Marco, in Florence. Most unwillingly the brethren submitted, and immediately Cosimo set architects and builders to work to erect a new convent, for the old one was in a ruinous state. The new cloisters offered a noble field to the genius of Fra Angelico, and he labored for their decoration with his whole soul; though the rule of the order was so strict that the pictures in the cells could be seen only by the monks, he put all his skill into them, and labored as devotedly as if the whole world could see and praise them, as indeed has since been done. His pictures in this convent are so numerous that we must not describe them, but will say that the Crucifixion in the chapter-room is usually called his masterpiece. It is nearly twenty-five feet square, and, besides the usual figures in this subject, the Saviour and the thieves, with the executioners, there are holy women, the founders of various orders, the patrons of the convent, and companies of saints. In the frame there are medallions with several saints and a Sibyl, each bearing an inscription from the prophecies relating to Christ's death; while below all, St. Dominic, the founder of the artist's order, bears a genealogical tree with many portraits of those who had been eminent among his followers. For this reason this picture has great historic value.
At last, in 1445, Pope Eugenius IV., who had dedicated the new convent of San Marco and seen the works of Angelico, summoned him to Rome. It is said that the Pope not only wished for some of his paintings, but he also desired to honor Angelico by giving him the archbishopric of Florence; but when this high position was offered him, Fra Angelico would not accept of it: he declared himself unequal to its duties, and begged the Pope to appoint Fra Antonino in his stead. This request was granted, and Angelico went on with his work as before, in all humility fulfilling his heaven-born mission to lead men to better lives through the sweet influence of his divine art.