The Holy Father gave a plenary indulgence in Santa Maria del Fiore for one day, from vespers on the 24th March till the next vespers, on the 25th March, which people availed themselves of with great devotion. The Cause of this was the preaching of Brother Antonio da Vergiegli in Santa Maria del Fiore during Lent, which bore good fruit.
(1) The provision is of the 16th March, 1478, Old Style, and perhaps the 25th is the day on which it was published. It was made to limit the concession of safe-conducts, and the causes which led to it may be read in the exordium which I have pleasure in publishing as a document which describes the way of thinking at that time. "The high and magnificent Signori having in mind how grave is the sin of homicide, by which man, a creature made and created in the image of God, is destroyed; and seeking the reasons why it is so very frequent under our jurisdiction; find among other things that it is encouraged by the facility of pardon and roper severity not being used in punishing such a detestable and abominable excess, he who commits the homicide being allowed to be continually in the presence of those who have suffered from the offence and of those who desire to live virtuously; none of whom can regard such manslayers without great indignation and perturbation of mind. And although the laws of the Florentine people bitterly avenge and punish such crimes, and give security against them; notwithstanding, whatever may be the reason, either too great humanity (which in reality one ought to call cruelty), or else undisciplined charity, such entirely right and just decrees are not properly observed. And the high Signori and discreet chief citizens wish to remedy these things which are so contrary to honest living and against divine laws, by making the fear of pubishment deter men from committing them, when they are deprived of all hope of pardon, and by adjuring the magistrates not only not to overlook such things, but to enforce the law with severity, hoping firmly that this provision may hav ea good effect" (State Archives of Florence, Consigli maggiori Provv. Reg. ad annum).
The term "Signori e Collegi" used in the decrees meant as follows: the Signori were the eight Priori and the Gonfaloniere della Giustizia, and the Collegi were the sixteen Gonfalonieri della Compagnie and the twelve men (three from each quarter) formerly called the twelve Buonuomini, who were summoned by the Signori to take council on almost every occasion. (Trans.)