This prayer is to be said while washing ones' hands in preparation for many of the other rites and rituals of the Religio Romana.
"Haec aqua a corpore impuritates, modo simile plumbo mutando ad aurum, elluat. Purga mentem. Purga carnem. Purga animum. Ita est!"
(Which, translated, means "May this water cast out all of my impurities from my substance as from lead to gold. Purify my mind, Purify my body, Purify my heart. It is so.")