We are now in the Fourth Sunday of Lent and one thing that you will notice if you are coming to church for mass is the color of the vestment that the priest is wearing. Why does the priest wear a rose vestment on this particular Sunday?
Well to begin with, there are two times during the year that a priest wears the rose vestment in the celebration of the mass. One is on the Fourth Sunday of Lent and the other one is on the Third Sunday of Advent. Why is that so?
Lent and Advent are commonly thought to be "penitential" seasons, as they are preparations which precede the Solemnity of the Resurrection of our Lord Jesus Christ (Easter Sunday) and the Solemnity of the Incarnation (Christmas). These penitential seasons were often accompanied by weeks of fasting. In some places, you may read that during these seasons there is a Sunday set aside in the midst of the fasting called a "Refreshment" Sunday, to have a break from the normal rigors of penitence. For Catholics, we called it Laetare Sunday on the fourth Sunday of Lent and Gaudete Sunday on the third Sunday of Advent.
Laetere means: “Rejoice”, and was taken from the introit of that Sunday in the Latin Mass: Laetare Jerusalem: et conventum facite omnes qui diligitis eam: gaudete cum laetitia, qui in tristitia fuistis: ut exsultetis,et satiemini ab uberibus consolationis vestrae. (Rejoice, O Jerusalem: and come together all you that love her: rejoice with joy, you that have been in sorrow: that you may exult, and be filled from the breasts of your consolation). This form of "rejoice" means "to be glad or joyful".
Gaudete also generally means: “Rejoice”, and also follows the introit for that Sunday in the Latin Mass: Gaudete in Domino semper: iterum dico, gaudete. Modestia vestra nota sit omnibus hominibus: Dominus enim prope est. Nihil solliciti sitis: sed in omni oratione petitiones vestræ innotescant apud Deum. Benedixisti Domine terram tuam: avertisti captivitatem Jacob. (Rejoice in the Lord always; again I say, rejoice. Let your forbearance be known to all, for the Lord is near at hand; have no anxiety about anything, but in all things, by prayer and supplication, with thanksgiving, let your requests be known to God. Lord, you have blessed your land; you have turned away the captivity of Jacob). This different form of rejoice also means to be joyful, although the tone leans more towards: "to aim joyfully toward", "to take a break", or to be joyful because there is "an end in sight".
So these two liturgical Sundays were intended to be an encouragement for those who had made it halfway through their fasting and other acts of piety to stick with it and make it the rest of the way through Easter and Christmas.