Remigius of Auxerre
Catena Aurea · Matthäusevangelium 3
Then went out to him Jerusalem, and all Judæa, and all the region round about Jordan, And were baptized of him in Jordan, confessing their sins.
The baptism of John bare a figure of the catechumens. As children are only catechized that they may become meet for the sacrament of Baptism; so John baptized, that they who were thus baptized might afterwards by a holy life become worthy of coming to Christ’s baptism. He baptized in Jordan, that the door of the Kingdom of Heaven might be there opened, where an entrance had been given to the children of Israel into the earthly kingdom of promise.