The Royal Gates, or Czar's Doors, set in the center of the iconostas', were so-called because Christ, the King of Glory as represented by his priests, enters the Royal Gates that lead to the altar. A curtain hung on the inside is drawn or opened during various parts of the divine service. Placed together, the doors depict the Annunciation at the top, where the Archangel Gabriel announces to the Virgin Mary that she is to become the mother of Jesus, the Son of God. The other four panels show the evangelists, Matthew, Mark, Luke, and John.