The Baptism of Christ by Master of the Saint Bartholomew Altar https://www.nga.gov/artworks/46177-baptism-christ
Saints played a very important role in the popular piety of the late Middle Ages. They were considered to be not only patrons and protectors against all manner of ills, but also mediators between the individual worshiper and God.
loincloth, stands in a shallow body of water facing another man who kneels on the bank