In the Book of Revelation, St. John writes,
Then I saw a new heaven and a new earth; for the first heaven and the first earth had passed away, and the sea was no more. And I saw the holy city, the new Jerusalem, coming down out of Heaven from God, prepared as a bride adorned for her husband. (Revelation 21:1-2)
Making the sign of the cross is very familiar to Catholics. It is one of the first things we learn about the faith. But what does it really mean to make the sign of the cross? Where does this practice come from?