start is with the Latin word sacramentum, which is a translation of the Greek work mysterion, meaning “a mystery,” that is, something that has been hidden but is now revealed. This admittedly doesn’t help us much, so perhaps we should turn to a simpler definition: A sacrament is “a visible sign of an invisible grace.” To take this a bit further, we can use the words of Augustine, who described a sacrament as a visible promise. The idea is that God is way beyond our capacity to understand: He is infinite,