Today we rejoice, because Easter, the Feast of our Salvation, is drawing near. Jerusalem, of which the Introit speaks, is the symbol on earth of our Mother, the Church, which is "God's House".
For while Christ is the One Redeemer (see the Epistle), the Church brings to us in the Sacraments the means whereby we receive all the benefits of Christ's sacrifice. So today is known by the name of the first word of the Introit: "Laetare!" (rejoice!).
We mark that mood of rejoicing by the Rose vestments, in contrast with the sombre and austere mood of the rest of Lent, to which we shall return from tomorrow until Easter.
~ Fr. Paul Dobson