The Church of Tau, dedicated to Sant'Antonio Abate, is characterised by the depiction of the saint's coat of arms as an old man with a long white beard holding a T-shaped stick and a piglet at his feet. This iconography is linked to the alleged healing power of pork fat, for which the brethren were known, and led to the coining of the phrase "Saint Anthony's fire". Also, the breeding of piglets by the friars played an important role in raising the figure of this saint to the status of protector of all domestic animals and patron of all rural activities.
The construction of the convent, which included the church dedicated to the saint, was carried out in the parish territory of San Giovanni Fuorcivitas in Pistoia, on the initiative of Fra Giovanni Guidotti, in the mid 14th century. Inside the building there are three main spaces: the covered garden (which was originally the convent's vegetable garden), the covered cloister and the church with the crypt below. Over the centuries, the complex underwent considerable transformations, culminating with the suppression of the order in 1774 and its subsequent sale to private citizens. It was not until the 1980s that the building was restored, re-establishing the original distribution of spaces.
The church has a single nave divided into three bays with a cross vault and an elevated presbytery, from which there is access to the crypt below with four sails resting on a central pillar. The walls feature an important cycle of frescoes, painted in 1372 by Niccolò di Tommaso with the collaboration of Antonio Vite, a pupil of Gherardo Starnina. A work that follows the ways of the Orcagna school and is designed to convey the aims of the order to the faithful. The twelve sails covering the church are dedicated to stories from the Holy Scriptures and the life of Saint Anthony Abbot. The entire complex reveals strong links with Florentine culture, as demonstrated by the use of pietra forte, the only case in the city.
Since 1990, the adjacent Palazzo del Tau has been home to the Marino Marini Foundation, which houses sculptures, paintings and drawings by the artist from Pistoia.