Objection 1. It would seem that also parish priests and archdeacons are more perfect than religious. For Chrysostom says in his Dialogue (De Sacerdot. vi): "Take for example a monk, such as Elias, if I may exaggerate somewhat, he is not to be compared with one who, cast among the people and compelled to carry the sins of many, remains firm and strong." A little further on he says: "If I were given the choice, where would I prefer to please, in the priestly office, or in the monastic solitude, without hesitation I should choose the former." Again in the same book (ch. 5) he says: "If you compare the toils of this project, namely of the monastic life, with a well-employed priesthood, you will find them as far distant from one another as a common citizen is from a king." Therefore it would seem that priests who have the cure of souls are more perfect than religious.
Objection 2. Further, Augustine says (ad Valerium, Ep. xxi): "Let thy religious prudence observe that in this life, and especially at these times, there is nothing so difficult, so onerous, so perilous as the office of bishop, priest, or deacon; while in God's sight there is no greater blessing, if one engage in the fight as ordered by our Commander-in-chief." Therefore religious are not more perfect than priests or deacons.
Objection 3. Further, Augustine says (Ep. lx, ad Aurel.): "It would be most regrettable, were we to exalt monks to such a disastrous degree of pride, and deem the clergy deserving of such a grievous insult," as to assert that 'a bad monk is a good clerk,' "since sometimes even a good monk makes a bad clerk." And a little before this he says that "God's servants," i.e. monks, "must not be allowed to think that they may easily be chosen for something better," namely the clerical state, "if they should become worse thereby," namely by leaving the monastic state. Therefore it would seem that those who are in the clerical state are more perfect than religious.
Objection 4. Further, it is not lawful to pass from a more perfect to a less perfect state. Yet it is lawful to pass from the monastic state to a priestly office with a cure attached, as appears (XVI, qu. i, can. Si quis monachus) from a decree of Pope Gelasius, who says: "If there be a monk, who by the merit of his exemplary life is worthy of the priesthood, and the abbot under whose authority he fights for Christ his King, ask that he be made a priest, the bishop shall take him and ordain him in such place as he shall choose fitting." And Jerome says (Ad Rustic. Monach., Ep. cxxv): "In the monastery so live as to deserve to be a clerk." Therefore parish priests and archdeacons are more perfect than religious.
Objection 5. Further, bishops are in a more perfect state than religious, as shown above (Article 7). But parish priests and archdeacons. through having cure of souls, are more like bishops than religious are. Therefore they are more perfect.
Objection 6. Further, virtue "is concerned with the difficult and the good" (Ethic. ii, 3). Now it is more difficult to lead a good life in the office of parish priest or archdeacon than in the religious state. Therefore parish priests and archdeacons have more perfect virtue than religious.
On the contrary, It is stated (XIX, qu. ii, cap. Duce): "If a man while governing the people in his church under the bishop and leading a secular life is inspired by the Holy Ghost to desire to work out his salvation in a monastery or under some canonical rule, since he is led by a private law, there is no reason why he should be constrained by a public law." Now a man is not led by the law of the Holy Ghost, which is here called a "private law," except to something more perfect. Therefore it would seem that religious are more perfect than archdeacons or parish priests.
I answer that, When we compare things in the point of super-eminence, we look not at that in which they agree, but at that wherein they differ. Now in parish priests and archdeacons three things may be considered, their state, their order, and their office. It belongs to their state that they are seculars, to their order that they are priests or deacons, to their office that they have the cure of souls committed to them.
Accordingly, if we compare these with one who is a religious by state, a deacon or priest by order, having the cure of souls by office, as many monks and canons regular have, this one will excel in the first point, and in the other points he will be equal. But if the latter differ from the former in state and office, but agree in order, such as religious priests and deacons not having the cure of souls, it is evident that the latter will be more excellent than the former in state, less excellent in office, and equal in order.
We must therefore consider which is the greater, preeminence of state or of office; and here, seemingly, we should take note of two things, goodness and difficulty. Accordingly, if we make the comparison with a view to goodness, the religious state surpasses the office of parish priest or archdeacon, because a religious pledges his whole life to the quest of perfection, whereas the parish priest or archdeacon does not pledge his whole life to the cure of souls, as a bishop does, nor is it competent to him, as it is to a bishop, to exercise the cure of souls in chief, but only in certain particulars regarding the cure of souls committed to his charge, as stated above (6, ad 2). Wherefore the comparison of their religious state with their office is like the comparisons of the universal with the particular, and of a holocaust with a sacrifice which is less than a holocaust according to Gregory (Hom. xx in Ezech.). Hence it is said (XIX, qu. i, can. Clerici qui monachorum.): "Clerics who wish to take the monastic vows through being desirous of a better life must be allowed by their bishops the free entrance into the monastery."
This comparison, however, must be considered as regarding the genus of the deed; for as regards the charity of the doer it happens sometimes that a deed which is of less account in its genus is of greater merit if it be done out of greater charity.
On the other hand, if we consider the difficulty of leading a good life in religion, and in the office of one having the cure of souls, in this way it is more difficult to lead a good life together with the exercise of the cure of souls, on account of outward dangers: although the religious life is more difficult as regards the genus of the deed, by reason of the strictness of religious observance. If, however, the religious is also without orders, as in the case of religious lay brethren, then it is evident that the pre-eminence of order excels in the point of dignity, since by holy orders a man is appointed to the most august ministry of serving Christ Himself in the sacrament of the altar. For this requires a greater inward holiness than that which is requisite for the religious state, since as Dionysius says (Eccl. Hier. vi) the monastic order must follow the priestly orders, and ascend to Divine things in imitation of them. Hence, other things being equal, a cleric who is in holy orders, sins more grievously if he do something contrary to holiness than a religious who is not in holy orders: although a religious who is not in orders is bound to regular observance to which persons in holy orders are not bound.
Reply to Objection 1. We might answer briefly these quotations from Chrysostom by saying that he speaks not of a priest of lesser order who has the cure of souls, but of a bishop, who is called a high-priest; and this agrees with the purpose of that book wherein he consoles himself and Basil in that they were chosen to be bishops. We may, however, pass this over and reply that he speaks in view of the difficulty. For he had already said: "When the pilot is surrounded by the stormy sea and is able to bring the ship safely out of the tempest, then he deserves to be acknowledged by all as a perfect pilot"; and afterwards he concludes, as quoted, with regard to the monk, "who is not to be compared with one who, cast among the people... remains firm"; and he gives the reason why, because "both in the calm end in the storm he piloted himself to safety." This proves nothing more than that the state of one who has the cure of souls is fraught with more danger than the monastic state; and to keep oneself innocent in face of a greater peril is proof of greater virtue. on the other hand, it also indicates greatness of virtue if a man avoid dangers by entering religion; hence he does not say that "he would prefer the priestly office to the monastic solitude," but that "he would rather please" in the former than in the latter, since this is a proof of greater virtue.
Reply to Objection 2. This passage quoted from Augustine also clearly refers to the question of difficulty which proves the greatness of virtue in those who lead a good life, as stated above (ad 1).
Reply to Objection 3. Augustine there compares monks with clerics as regards the pre-eminence of order, not as regards the distinction between religious and secular life.
Reply to Objection 4. Those who are taken from the religious state to receive the cure of souls, being already in sacred orders, attain to something they had not hitherto, namely the office of the cure, yet they do not put aside what they had already. For it is said in the Decretals (XVI, qu. i, can. De Monachis): "With regard to those monks who after long residence in a monastery attain to the order of clerics, we bid them not to lay aside their former purpose."
On the other hand, parish priests and archdeacons, when they enter religion, resign their cure, in order to enter the state of perfection. This very fact shows the excellence of the religious life. When religious who are not in orders are admitted to the clerical state and to the sacred orders, they are clearly promoted to something better, as stated: this is indicated by the very way in which Jerome expresses himself: "So live in the monastery as to deserve to be a clerk."
Reply to Objection 5. Parish priests and archdeacons are more like bishops than religious are, in a certain respect, namely as regards the cure of souls which they have subordinately; but as regards the obligation in perpetuity, religious are more like a bishop, as appears from what we have said above (A5,6).
Reply to Objection 6. The difficulty that arises from the arduousness of the deed adds to the perfection of virtue; but the difficulty that results from outward obstacles sometimes lessens the perfection of virtue--for instance, when a man loves not virtue so much as to wish to avoid the obstacles to virtue, according to the saying of the Apostle (1 Corinthians 9:25), "Everyone that striveth for the mastery refraineth himself from all things": and sometimes it is a sign of perfect virtue--for instance, when a man forsakes not virtue, although he is hindered in the practice of virtue unawares or by some unavoidable cause. On the religious state there is greater difficulty arising from the arduousness of deeds; whereas for those who in any way at all live in the world, there is greater difficulty resulting from obstacles to virtue, which obstacles the religious has had the foresight to avoid.
Source: Summa Theologica (New Advent)