In Christian jargon, a baptismal “font” is not a fancy script that you chose to write your Facebook entry. Instead, it is the receptacle in which holy water is held for baptism in denominations who do not use immersion but instead use aspersion (sprinkling) or affusion (pouring). Although the shape is highly variable, many are eight-sided as a reminder that Christ rose on the eighth day. Fonts are often placed near the church’s entrance to remind believers of their baptism as they enter. Traditionally, the person entering the church will dip their first two fingers into the font’s water and make the sign of the cross with their fingers as a remembrance of their baptism and also to bless themselves in preparation for worship. In Medieval churches, a separate building, called a baptistery, housed the font. The earliest baptisteries contained a font designed for full immersion that was cross-shaped with three steps (for the Trinity) leading into them. After Vatican II, the Catholic Church has encouraged fonts that are suitable for full immersion of an infant and for at least the pouring of water over the whole body of an adult.
~Dr. Gil Haas