Baptismal font: function and use

The ritual of baptism has evolved throughout the history of Christianity. Initially practiced by complete immersion in living water, meaning running water, the rite of effusion later imposed itself, impacting the shape of the baptismal furnishings. 

Originally practiced in a stream, on the model of Christ's baptism, Christians created spaces reserved for this practice from the 4th century onwards: baptisteries. These were placed outside churches and consisted of a baptismal pool dug into the ground. When the rite of effusion was required, baptism was performed above basins, called "baptismal fonts", which were generally integrated into the church. 

The existence of stone baptismal fonts such as the one at Cousolre is not attested until the 12th century, and it is likely that they were previously built of wood. It was in 852, at the Synod of Rheims, that Archbishop Hincmar advocated the choice of stone, which was again affirmed in 1290 by the liturgist Guillaume Durand, who this time gave symbolic reasons for this choice, in line with the thought of Paulinus, Bishop of Nole (394-431): "He himself (Christ), the rock of the Church stands on the rock from which flow four sonorous springs, the evangelists, the living rivers of Christ".

Lexicon :

Synod: assembly of ecclesiastics