““As Tertullian put it, “We make the sign of the cross on our foreheads at every turn, at our going in or coming out of the house . . . and in all ordinary actions of daily life.” 120 The pagans saw Christians do this, mocked it, and could view it as suspicious activity. But Christians believed that it had the protective power of a spiritual breastplate. The apprentice Christians needed to learn how to make the sign of the cross, when to make it, when to be seen making it, and when to do it invisibly.””
