It has been the custom of the Catholic Church, to veil the crosses and the images of the saints from the 5th Sunday of Lent until Easter.
Why are these veiled?
In the past, the gospel read on the 5th Sunday of Lent ended with Christ hiding himself from the Jewish authorities who wanted to stone him (John 8:59), so now he is hidden from the world in preparation for the mysteries of his passion. The statues of the saints, too, are covered; for it is but just that, if the glory of the Master be eclipsed, the servant should not appear. The veiling of the crucifix also expresses the humiliation to which our Saviour subjected himself. The crosses will be unveiled on Good Friday whereas the Statues will be unveiled on Holy Saturday before the Easter Vigil service.