In S. Maria del Fiore he painted the image of Niccolò da Tolentino on horseback; and while he was working at this a boy who was passing shook his ladder, whereupon he flew into such a rage, like the brutal man that he was, that he jumped down and ran after him as far as the Canto de' Pazzi. In the cemetery of S. Maria Nuova, also, below the Ossa, he painted a S. Andrew, which gave so much satisfaction that he was afterwards commissioned to paint the Last Supper of Christ with His Apostles in the refectory, where the nurses and other attendants have their meals. Having acquired favour through this work with the house of Portinari and with the Director of the hospital, he was appointed to paint a part of the principal chapel, of which another part was allotted to Alesso Baldovinetti, and the third to the then greatly celebrated painter Domenico da Venezia, who had been summoned to Florence by reason of the new method that he knew of painting in oil. Now, while each of them applied himself to his part of the work, Andrea was very envious of Domenico, because, while knowing himself to be superior to the other in design, he was much displeased that the Venetian, although a foreigner, should be welcomed and entertained by the citizens; wherefore anger and disdain moved him so strongly, that he began to think whether he could not in one way or another remove him from his path. Andrea was no less crafty in dissimulation than he was excellent in painting, being cheerful of countenance at his pleasure, ready of speech, fiery in spirit, and as resolute in every bodily action as he was in mind; he felt towards others as he did towards Domenico, and, if he saw some error in the works of other craftsmen, he was wont to mark it secretly with his nail. And in his youth, when his works were criticized in any respect, he would give the critics to know by means of blows and insults that he was ever able and willing to take revenge in one way or another for any affront.
But let us say something of Domenico, before we come to the work of the said chapel. Before coming to Florence, Domenico had painted some pictures with much grace in the Sacristy of S. Maria at Loreto, in company with Piero della Francesca; which pictures, besides what he had wrought in other places (such as an apartment in the house of the Baglioni in Perugia, which is now in ruins), had made his fame known in Florence. Being summoned to that city, before doing anything else, he painted a Madonna in the midst of some saints, in fresco, in a shrine on the Canto de' Carnesecchi, at the corner of two streets, of which one leads to the new Piazza di S. Maria Novella and the other to the old. This work, being approved and greatly extolled by the citizens and by the craftsmen of those times, caused even greater disdain and envy to blaze up in the accursed mind of Andrea against poor Domenico; wherefore Andrea, having determined to effect by deceit and treachery what he could not carry out openly without manifest peril to himself, pretended to be very much the friend of Domenico, who, being a good and affectionate fellow, fond of singing and devoted to playing on the lute, received him as a friend very willingly, thinking Andrea to be a clever and amusing person. And so, continuing this friendship, so true on one side and so false on the other, they would come together every night to make merry and to serenade their mistresses; and this gave great delight to Domenico, who, loving Andrea sincerely, taught him the method of colouring in oil, which as yet was not known in Tuscany.