Purification with water -- a venerable Pagan sacrament Purification -- from unclean foods, or acts, or contacts -- is an idea so old it fades into pre-history. Pagans purified themselves with fire, incense, blood sacrifice, they even purified themselves with a winnowing fan or sea onions! But the most used, most widespread tool of pagan purification was...water.
Pagan water purification rituals were used in the archaic Near East and are written about in the Old Testament. Homer mentions the washing of hands before prayer, and the purification of an entire army with water [Iliad, 1.313]. The Greeks even has priests, kathartai, who specialized in purification with water. After the conspiracy of Cylon in Athens in 632 BC, a fellow named Epimenides of Crete purified the entire city -- with water [Diogines Laertius 1.10.3].
The ancient Church Father Tertullian, noting that Pagan baptism preceded the Christian sacrament, describes purifying water's several Pagan uses:
- initiation into the mystery religions -- i.e. baptism
- purifying temples and even cities
- washing away sin (!!)