In ancient times, all men over fifteen years had to bring a candle to the Baptistery and for the occasion they lavishly decorated houses, palaces, warehouses.
At the time also Piazza del Duomo, between the church of Santa Reparata and the Baptistery, was covered with a large canvas supported by tight ropes (a custom that was interrupted at the end of the fifteenth century due to a fire and an impetuous storm) and on the eve there was an important procession.
After the first Vespers (evening of the 23rd) the offering of votive gifts took place, especially candles.
A part of them was burned inside the Baptistery throughout the year, while the remaining ones were sold and with the money obtained the church was maintained and embellished.
The candles were donated not only by the Signoria, but also by the Magistrature of the Republic, by the various Arts, by the secular and religious companies and by the “lands” submitted by the Florentines who, at the signing of the surrender treaty, imposed on the Municipality or the conquered castle to offer a candle, a palio or other taxes (consisting of silver or other objects or even animals).
During the ceremony the huge candles were transported by hand or by wagons, if, as often happened, they were adorned with imposing figures in papier-mâché or painted wood, and then offered to the saint.
The traditional offer of candles, although simplified, has come down to the present day: on the morning of of June 24, in fact, a procession formed by the families of the Municipality, the traffic police, the valets and the Deputation of the Society of San Giovanni Battista, the mayor and other authorities, who head to the banner of Florence and that of San Giovanni, starts from Palazzo Vecchio, towards the Baptistery.
These representatives are received in the Baptistery by the clergy of the cathedral, who go there at 10 am of the feast to sing a part (Third) of the divine office in honor of the Patron and then, with the clergy, joined by the civil representatives and the Deputation of St. John, to return in procession to Santa Maria del Fiore for the solemn Mass of 10.30.