Ad orientem is Latin for “toward the East.” It refers to the direction that the priest faces during particular moments in the Holy Sacrifice of the Mass. Historically, Catholic churches have always been built along an East-West axis whenever possible, the East being the direction from which the early Christians believed the Lord would come in His glory (specifically the Mount of Olives, the site of His Ascension). The priest stands with his people on the same side of the altar so that, together facing the East of the sacred liturgy, they could offer the pleasing sacrifice of their lives (cf. Romans 12.1) in union with the priest offering the sacrifice of Christ.