26 We feel the deepest joy at the thought of the innumerable army of virgins and apostles who, from the first centuries of the Church up to our own day, have given up marriage to devote themselves more easily and fully to the salvation of their neighbor for the love of Christ, and have thus been enabled to undertake and carry through admirable works of religion and charity. We by no means wish to detract from the merits and apostolic fruits of the active members of Catholic Action: by their zealous efforts they can often touch souls that priests and religious cannot gain. Nevertheless, works of charity are for the most part the field of action of consecrated persons. These generous souls are to be found laboring among men of every age and condition, and when they fall worn out or sick, they bequeath their sacred mission to others who take their place. Hence it often happens that a child, immediately after birth, is placed in the care of consecrated persons, who supply in so far as they can for a mother's love; at the age of reason he is entrusted to educators who see to his Christian instruction together with the development of his mind and the formation of his character; if he is sick, the child or adult will find nurses moved by the love of Christ who will care for him with unwearying devotion; the orphan, the person fallen into material destitution or moral abjection, the prisoner, will not be abandoned. Priests, religious, consecrated virgins will see in him a suffering member of Christ's Mystical Body, and recall the words of the Divine Redeemer: "For I was hungry, and you gave me to eat; I was thirsty, and you gave me to drink; I was a stranger, and you took me in; naked, and you covered me; sick, and you visited me; I was in prison, and you came to me. . . Amen I say to you, as long you did it to one of these my least brethren, you did it to me." Who can ever praise enough the missionaries who toil for the conversion of the pagan multitudes, exiles from their native country, or the nuns who render them indispensable assistance?" To each and every one We gladly apply these words of Our Apostolic Exhortation, "Menti Nostrae:" ". . . by this law of celibacy the priest not only does not abdicate his paternity, but increases it immensely, for he begets not for an earthly and transitory life but for the heavenly and eternal one."
Source: Sacra Virginitas (Vatican.va)