What is Passion Sunday?
The fifth Sunday of Lent (Passion Sunday) is called Dominica de Passione in the Roman Missal, and Dominica Passionis in the Breviary. It is also known as Judica Sunday, from the first word of the Introit of Mass. Since after this Sunday there are not many more days of the Lenten season the Greek Church admonishes the faithful to special mortifications, and places before them the example of the penitent St. Mary of Egypt.
Why are the Statues Covered?
Passion Sunday is also the beginning of Passiontide. All crucifixes and images may be covered in veils (usually violet, the color of vestments in Lent) starting on Passion Sunday. The crosses are to be covered until the end of the celebration of the Lord's passion on Good Friday. Statues and images remain covered until the beginning of the Easter Vigil. Specifically, those veils are removed during the singing of the Gloria. The veiling was associated with Passion Sunday's Gospel (John 8:46–59), in which Jesus "hid himself" from the people.