The meeting and composition of the brigata is full of numerological significance to indicate the extent to which God's hand seems to be everywhere and yet unrecognized in the Decameron. First off, they meet in the church of Santa Maria Novella. The year itself in which they meet is during the time of the Black Plague, 1348. The first and last number add up to 9, while the middle numbers add up to 7. There are 7 ladies and 3 men. The oldest lady is 27 (9x3 or 3x3x3) and the youngest 18 (9x2 or 3x3x2): the difference between their being ages 9. The women are introduced in a group of 4 and a group of 3. This grouping of the virtues is already seen in other works of Boccaccio, such as the Filocolo. Ferrante notes that Boccaccio had in mind Purgatorio XXIX in the Divine Comedy where the Cardinal Virtues (Prudence, Temperance, Fortitude, and Justice) are first introduced dancing on one side of Beatrice's chariot, then the Theological (Faith, Hope, and Charity) on the other. The women are marked in this division by those who bring a serving maid (the Cardinal Virtues) and those who do not (Theological Virtues). Furthermore, the Theological Virtues rule over the 3rd, 6th and 9th days, a clear play on the number 3 since there are three of them and they rule the days in multiples of three. Thus the company adds up to the 10 members who tell 10 stories each over a course of 10 story days. Bernardo argues that the numerological signs appear to point to the presence of the Holy Trinity, the labors involved in the seven days of creation and the seven virtues. However, the brigata prepares for ten days of festivities without realizing the inherent numerological significance. This ignorance might perhaps allude to the spiritual blindness of the brigata.
(B. C.) adapted from: Bernardo, Aldo S. "The Plague as Key to Meaning in Boccaccio's Decameron," in: The Black Death. Daniel Williman, ed. Binghamton, New York: Medieval & Renaissance Texts & Studies, 1982. pp 39-64. Ferrante, Joan M. "The Frame Characters of the Decameron: A Progression of Virtues." Romance Philology 19.2 (1965).