The text refers to a religious ritual called the "Elevation of the Chalice" that takes place on Easter Sunday, which is a Christian holiday celebrating the resurrection of Jesus Christ.
The chalice is a cup-shaped vessel used during the Catholic Eucharist, which is a sacrament that commemorates the Last Supper of Jesus with his disciples. During the Eucharist, wine is consecrated and becomes the blood of Christ, which is then consumed by the faithful.
The "Elevation" of the Chalice refers to the moment when the priest or minister raises the chalice above their head as a symbolic gesture of offering the blood of Christ to God. This is often accompanied by prayers and hymns.