<P> According to Pisani, Giotto painted the chapel's inner surface following a comprehensive iconographic and decorative project devised by the Augustinian theologian, Friar Alberto da Padova . Among the sources utilized by Giotto following Friar Alberto's advice are the Apocryphal Gospels of Pseudo-Matthew and Nicodemus, the Golden Legend (Legenda aurea) by Jacopo da Varazze (Jacobus a Varagine) and, for a few minute iconographic details, Pseudo-Bonaventure's Meditations on the Life of Jesus Christ, as well as a number of Augustinian texts, such as De doctrina Christiana, De libero arbitrio, De Genesi contra Manicheos, De quantitate animae, and other texts from the Medieval Christian tradition, among which is the Phisiologus . </P> <P> Most Giotto scholarship believes that Giotto had made a number of theological mistakes . For instance, Giotto placed Hope after Charity in the Virtues series, and did not include Avarice in the Vices series, due to the usual representation of Enrico Scrovegni as a usurer . Giuliano Pisani asserts that Giotto followed a careful and deliberate theological programme based on Saint Augustine and devised by Friar Alberto da Padova . Avarice, far from being "absent" in Giotto's cycle, is portrayed with Envy, forming with it a fundamental component of a more comprehensive sin . For this reason Envy is placed facing the virtue of Charity, to indicate that Charity is the exact opposite of Envy, and that in order to cure oneself of the sin of Envy one needs to learn from Charity . Charity crushes Envy's money bag under her feet, while on the opposite wall red flames burn under Envy's feet . </P> <P> Giotto frescoed the chapel's whole surface, including the walls and the ceiling . The fresco cycle is organised along four tiers, each of which contains episodes from the stories of the various protagonists of the Sacred History . Each tier is divided into frames, each forming a scene . The chapel is asymmetrical in shape, with six windows on the longer south wall, and this shape determined the layout of the decoration . The first step was choosing to place two frames between each double window set on the south wall; secondly, the width and height of the tiers was fixed in order to calculate the same space on the opposite north wall . </P> <P> Cycles of scenes showing the Life of Christ and the Life of the Virgin were the grandest form of religious art in the period, and Giotto's cycle is unusually large and comprehensive, showing the ambition of the commission . Allowing for this, the selection and iconography of the scenes is broadly comparable to other contemporary cycles; Giotto's innovation lies in the monumentality of his forms and the clarity of his compositions . </P>

The frescos in the scrovegni chapel depict stories from