Again, "a holocaust is the offering to God of all that one has," according to Gregory (Hom. xx in Ezech.). Now man has a threefold good, according to the Philosopher (Ethic. i, 8). First, the good of external things, which he wholly offers to God by the vow of voluntary poverty: secondly, the good of his own body, and this good he offers to God especially by the vow of continence, whereby he renounces the greatest bodily pleasures. The third is the good of the soul, which man wholly offers to God by the vow of obedience, whereby he offers God his own will by which he makes use of all the powers and habits of the soul. Therefore the religious state is fittingly constituted by the three vows.
Reply Obj. 1: As stated above (A. 1), the end whereunto the religious vow is directed is the perfection of charity, since all the interior acts of virtue belong to charity as to their mother, according to 1 Cor. 13:4, "Charity is patient, is kind," etc. Hence the interior acts of virtue, for instance humility, patience, and so forth, do not come under the religious vow, but this is directed to them as its end.
Reply Obj. 2: All other religious observances are directed to the three aforesaid principal vows; for if any of them are ordained for the purpose of procuring a livelihood, such as labor, questing, and so on, they are to be referred to poverty; for the safeguarding of which religious seek a livelihood by these means. Other observances whereby the body is chastised, such as watching, fasting, and the like, are directly ordained for the observance of the vow of continence. And such religious observances as regard human actions whereby a man is directed to the end of religion, namely the love of God and his neighbor (such as reading, prayer, visiting the sick, and the like), are comprised under the vow of obedience that applies to the will, which directs its actions to the end according to the ordering of another person. The distinction of habit belongs to all three vows, as a sign of being bound by them: wherefore the religious habit is given or blessed at the time of profession.
Reply Obj. 3: By obedience a man offers to God his will, to which though all human affairs are subject, yet some are subject to it alone in a special manner, namely human actions, since passions belong also to the sensitive appetite. Wherefore in order to restrain the passions of carnal pleasures and of external objects of appetite, which hinder the perfection of life, there was need for the vows of continence and poverty; but for the ordering of one's own actions accordingly as the state of perfection requires, there was need for the vow of obedience.
Reply Obj. 4: As the Philosopher says (Ethic. iv, 3), strictly and truly speaking honor is not due save to virtue. Since, however, external goods serve instrumentally for certain acts of virtue, the consequence is that a certain honor is given to their excellence especially by the common people who acknowledge none but outward excellence. Therefore since religious tend to the perfection of virtue it becomes them not to renounce the honor which God and all holy men accord to virtue, according to Ps. 138:17, "But to me Thy friends, O God, are made exceedingly honorable." On the other hand, they renounce the honor that is given to outward excellence, by the very fact that they withdraw from a worldly life: hence no special vow is needed for this. _______________________
EIGHTH ARTICLE [II-II, Q. 186, Art. 8]
Whether the Vow of Obedience Is the Chief of the Three Religious Vows?
Objection 1: It would seem that the vow of obedience is not the chief of the three religious vows. For the perfection of the religious life was inaugurated by Christ. Now Christ gave a special counsel of poverty; whereas He is not stated to have given a special counsel of obedience. Therefore the vow of poverty is greater than the vow of obedience.
Obj. 2: Further, it is written (Ecclus. 26:20) that "no price is worthy of a continent soul." Now the vow of that which is more worthy is itself more excellent. Therefore the vow of continence is more excellent than the vow of obedience.
Obj. 3: Further, the greater a vow the more indispensable it would seem to be. Now the vows of poverty and continence "are so inseparable from the monastic rule, that not even the Sovereign Pontiff can allow them to be broken," according to a Decretal (De Statu Monach., cap. Cum ad monasterium): yet he can dispense a religious from obeying his superior. Therefore it would seem that the vow of obedience is less than the vow of poverty and continence.