A small wall shrine/reliquary shows shutters that are known as wings.  A statue of the Virgin and Child is in the center.  The wings can fold over to hide the statue from view.  The opening and closing of veils and shutters that enclosed statues and paintings was a common element of ritual worship.  The hiding of art and its revelation at precise moment in liturgy were standard practices for centuries.  See, as an exemplar the three-level unfolding of the Isenheim Altarpiece by Matthias Grünewald, 1510-15, now Musée Unterdenlinden, Colmar, France.  The first level, closed, shows the Crucifixion and Entombment of Christ, the second, the Annunciation and Nativity, and the third level the statues of saints Anthony with Paul and Jerome, the carving of Christ at the Last Supper and paintings of Saints Paul and Anthony in the Desert and the Temptation of St Anthony.  (web gallery of art) back to "worship"