Does anyone know of any resources (online or otherwise) that discuss the evolution of the use of holy water in Christianity? For example, Eastern churches do not have holy water fonts at the entrance of churches/cathedrals, while Roman Catholic churches do. When did this practice develop? Also, what is the liturgical use of holy water in the East in general? I'm specifically also interested in any evolution or connection with ancient Jewish practices. For example, I know that the temple had a place to wash. This would seem to mirror the Roman Catholic practice of blessing oneself with water at the entrance of a church.