Reply Obj. 1: The commandment of honoring our parents extends not only to bodily but also to spiritual service, and to the paying of deference. Hence even those who are in religion can fulfil the commandment of honoring their parents, by praying for them and by revering and assisting them, as becomes religious, since even those who live in the world honor their parents in different ways as befits their condition.
Reply Obj. 2: Since slavery was imposed in punishment of sin, it follows that by slavery man forfeits something which otherwise he would be competent to have, namely the free disposal of his person, for "a slave belongs wholly to his master" [*Aristotle, Polit. i, 2]. On the other hand, the son, through being subject to his father, is not hindered from freely disposing of his person by transferring himself to the service of God; which is most conducive to man's good.
Reply Obj. 3: He who is under a certain fixed obligation cannot lawfully set it aside so long as he is able to fulfil it. Wherefore if a person is under an obligation to give an account to someone or to pay a certain fixed debt, he cannot lawfully evade this obligation in order to enter religion. If, however, he owes a sum of money, and has not wherewithal to pay the debt, he must do what he can, namely by surrendering his goods to his creditor. According to civil law [*Cod. IV, x, de Oblig. et Action, 12] money lays an obligation not on the person of a freeman, but on his property, because the person of a freeman "is above all pecuniary consideration" [*Dig. L, xvii, de div. reg. Jur. ant. 106, 176]. Hence, after surrendering his property, he may lawfully enter religion, nor is he bound to remain in the world in order to earn the means of paying the debt.
On the other hand, he does not owe his father a special debt, except as may arise in a case of necessity, as stated above. _______________________
SEVENTH ARTICLE [II-II, Q. 189, Art. 7]
Whether Parish Priests May Lawfully Enter Religion?
Objection 1: It would seem that parish priests cannot lawfully enter religion. For Gregory says (Past. iii, 4) that "he who undertakes the cure of souls, receives an awful warning in the words: 'My son, if thou be surety for thy friend, thou hast engaged fast thy hand to a stranger'" (Prov. 6:1); and he goes on to say, "because to be surety for a friend is to take charge of the soul of another on the surety of one's own behavior." Now he who is under an obligation to a man for a debt, cannot enter religion, unless he pay what he owes, if he can. Since then a priest is able to fulfil the cure of souls, to which obligation he has pledged his soul, it would seem unlawful for him to lay aside the cure of souls in order to enter religion.
Obj. 2: Further, what is lawful to one is likewise lawful to all. But if all priests having cure of souls were to enter religion, the people would be left without a pastor's care, which would be unfitting. Therefore it seems that parish priests cannot lawfully enter religion.
Obj. 3: Further, chief among the acts to which religious orders are directed are those whereby a man gives to others the fruit of his contemplation. Now such acts are competent to parish priests and archdeacons, whom it becomes by virtue of their office to preach and hear confessions. Therefore it would seem unlawful for a parish priest or archdeacon to pass over to religion.
On the contrary, It is said in the Decretals (XIX, qu. ii, cap. Duce sunt leges.): "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, even though his bishop withstand him, we authorize him to go freely."