Entering the Sacristy one can follow the life of St. Benedict in the frescos commissioned by Benedetto degli Alberti, the first undertaking of the Olivetans who arrived at San Miniato in 1373.
The entire decoration of the sacristy (1387 -1388) is attributed to Spinello Aretino b. ca. 1345, Arezzo, d. 1410, Arezzo.
The cycle of the scenes is illustrated in chronological sequence almost like a film. (Cf. the life of Saint Francis at Assisi by Giotto). The life of the saint is taken from "Dialogues" of Gregory the Great and from "Golden Legend" by Jacopo da Varagine.
The images below are from http://www.wga.hu/frames-e.html?/html/s/spinello/index.html