Objection 1. It would seem that the twelve degrees of humility that are set down in the Rule of the Blessed Benedict [St. Thomas gives these degrees in the reverse order to that followed by St. Benedict] are unfittingly distinguished. The first is to be "humble not only in heart, but also to show it in one's very person, one's eyes fixed on the ground"; the second is "to speak few and sensible words, and not to be loud of voice"; the third is "not to be easily moved, and disposed to laughter"; the fourth is "to maintain silence until one is asked"; the fifth is "to do nothing but to what one is exhorted by the common rule of the monastery"; the sixth is "to believe and acknowledge oneself viler than all"; the seventh is "to think oneself worthless and unprofitable for all purposes"; the eighth is "to confess one's sin"; the ninth is "to embrace patience by obeying under difficult and contrary circumstances"; the tenth is "to subject oneself to a superior"; the eleventh is "not to delight in fulfilling one's own desires"; the twelfth is "to fear God and to be always mindful of everything that God has commanded." For among these there are some things pertaining to the other virtues, such as obedience and patience. Again there are some that seem to involve a false opinion--and this is inconsistent with any virtue--namely to declare oneself more despicable than all men, and to confess and believe oneself to be in all ways worthless and unprofitable. Therefore these are unfittingly placed among the degrees of humility.
Objection 2. Further, humility proceeds from within to externals, as do other virtues. Therefore in the aforesaid degrees, those which concern outward actions are unfittingly placed before those which pertain to inward actions.
Objection 3. Further, Anselm (De Simil. ci, seqq.) gives seven degrees of humility, the first of which is "to acknowledge oneself contemptible"; the second, "to grieve for this"; the third, "to confess it"; the fourth, "to convince others of this, that is to wish them to believe it"; the fifth, "to bear patiently that this be said of us"; the sixth, "to suffer oneself to be treated with contempt"; the seventh, "to love being thus treated." Therefore the aforesaid degrees would seem to be too numerous.
Objection 4. Further, a gloss on Matthew 3:15 says: "Perfect humility has three degrees. The first is to subject ourselves to those who are above us, and not to set ourselves above our equals: this is sufficient. The second is to submit to our equals, and not to set ourselves before our inferiors; this is called abundant humility. The third degree is to subject ourselves to inferiors, and in this is perfect righteousness." Therefore the aforesaid degrees would seem to be too numerous.
Objection 5. Further, Augustine says (De Virginit. xxxi): "The measure of humility is apportioned to each one according to his rank. It is imperiled by pride, for the greater a man is the more liable is he to be entrapped." Now the measure of a man's greatness cannot be fixed according to a definite number of degrees. Therefore it would seem that it is not possible to assign the aforesaid degrees to humility.
I answer that, As stated above (Article 2) humility has essentially to do with the appetite, in so far as a man restrains the impetuosity of his soul, from tending inordinately to great things: yet its rule is in the cognitive faculty, in that we should not deem ourselves to be above what we are. Also, the principle and origin of both these things is the reverence we bear to God. Now the inward disposition of humility leads to certain outward signs in words, deeds, and gestures, which manifest that which is hidden within, as happens also with the other virtues. For "a man is known by his look, and a wise man, when thou meetest him, by his countenance" (Sirach 19:26). Wherefore the aforesaid degrees of humility include something regarding the root of humility, namely the twelfth degree, "that a man fear God and bear all His commandments in mind."
Again, they include certain things with regard to the appetite, lest one aim inordinately at one's own excellence. This is done in three ways. First, by not following one's own will, and this pertains to the eleventh degree; secondly, by regulating it according to one's superior judgment, and this applies to the tenth degree; thirdly, by not being deterred from this on account of the difficulties and hardships that come in our way, and this belongs to the ninth degree.
Certain things also are included referring to the estimate a man forms in acknowledging his own deficiency, and this in three ways. First by acknowledging and avowing his own shortcomings; this belongs to the eighth degree: secondly, by deeming oneself incapable of great things, and this pertains to the seventh degree: thirdly, that in this respect one should put others before oneself, and this belongs to the sixth degree.
Again, some things are included that refer to outward signs. One of these regards deeds, namely that in one's work one should not depart from the ordinary way; this applies to the fifth degree. Two others have reference to words, namely that one should not be in a hurry to speak, which pertains to the fourth degree, and that one be not immoderate in speech, which refers to the second. The others have to do with outward gestures, for instance in restraining haughty looks, which regards the first, and in outwardly checking laughter and other signs of senseless mirth, and this belongs to the third degree.
Reply to Objection 1. It is possible, without falsehood, to deem and avow oneself the most despicable of men, as regards the hidden faults which we acknowledge in ourselves, and the hidden gifts of God which others have. Hence Augustine says (De Virginit. lii): "Bethink you that some persons are in some hidden way better than you, although outwardly you are better than they." Again, without falsehood one may avow and believe oneself in all ways unprofitable and useless in respect of one's own capability, so as to refer all one's sufficiency to God, according to 2 Corinthians 3:5, "Not that we are sufficient to think anything of ourselves as of ourselves: but our sufficiency is from God." And there is nothing unbecoming in ascribing to humility those things that pertain to other virtues, since, just as one vice arises from another, so, by a natural sequence, the act of one virtue proceeds from the act of another.
Reply to Objection 2. Man arrives at humility in two ways. First and chiefly by a gift of grace, and in this way the inner man precedes the outward man. The other way is by human effort, whereby he first of all restrains the outward man, and afterwards succeeds in plucking out the inward root. It is according to this order that the degrees of humility are here enumerated.
Reply to Objection 3. All the degrees mentioned by Anselm are reducible to knowledge, avowal, and desire of one's own abasement. For the first degree belongs to the knowledge of one's own deficiency; but since it would be wrong for one to love one's own failings, this is excluded by the second degree. The third and fourth degrees regard the avowal of one's own deficiency; namely that not merely one simply assert one's failing, but that one convince another of it. The other three degrees have to do with the appetite, which seeks, not outward excellence, but outward abasement, or bears it with equanimity, whether it consist of words or deeds. For as Gregory says (Regist. ii, 10, Ep. 36), "there is nothing great in being humble towards those who treat us with regard, for even worldly people do this: but we should especially be humble towards those who make us suffer," and this belongs to the fifth and sixth degrees: or the appetite may even go so far as lovingly to embrace external abasement, and this pertains to the seventh degree; so that all these degrees are comprised under the sixth and seventh mentioned above.
Reply to Objection 4. These degrees refer, not to the thing itself, namely the nature of humility, but to the degrees among men, who are either of higher or lower or of equal degree.
Reply to Objection 5. This argument also considers the degrees of humility not according to the nature of the thing, in respect of which the aforesaid degrees are assigned, but according to the various conditions of men.
Source: Summa Theologica (New Advent)