Objection 1. It would seem that the difference of states does not apply to those who are beginning, progressing, or perfect. For "diverse genera have diverse species and differences" [Aristotle, Categ. ii]. Now this difference of beginning, progress, and perfection is applied to the degrees of charity, as stated above (Question 24, Article 09), where we were treating of charity. Therefore it would seem that the differences of states should not be assigned in this manner.
Objection 2. Further, as stated above (Article 1), state regards a condition of servitude or freedom, which apparently has no connection with the aforesaid difference of beginning, progress, and perfection. Therefore it is unfitting to divide state in this way.
Objection 3. Further, the distinction of beginning, progress, and perfection seems to refer to "more" and "less," and this seemingly implies the notion of grades. But the distinction of grades differs from that of states, as we have said above (A2,3). Therefore state is unfittingly divided according to beginning, progress, and perfection.
On the contrary, Gregory says (Moral. xxiv, 11): "There are three states of the converted, the beginning, the middle, and the perfection"; and (Hom. xv in Ezech.): "Other is the beginning of virtue, other its progress, and other still its perfection."
I answer that, As stated above (Article 1) state regards freedom or servitude. Now in spiritual things there is a twofold servitude and a twofold freedom: for there is the servitude of sin and the servitude of justice; and there is likewise a twofold freedom, from sin, and from justice, as appears from the words of the Apostle (Romans 6:20-22), "When you were the servants of sin, you were free men to justice... but now being made free from sin," you are... "become servants to God."
Now the servitude of sin or justice consists in being inclined to evil by a habit of sin, or inclined to good by a habit of justice: and in like manner freedom from sin is not to be overcome by the inclination to sin, and freedom from justice is not to be held back from evil for the love of justice. Nevertheless, since man, by his natural reason, is inclined to justice, while sin is contrary to natural reason, it follows that freedom from sin is true freedom which is united to the servitude of justice, since they both incline man to that which is becoming to him. On like manner true servitude is the servitude of sin, which is connected with freedom from justice, because man is thereby hindered from attaining that which is proper to him. That a man become the servant of justice or sin results from his efforts, as the Apostle declares (Romans 6:16): "To whom you yield yourselves servants to obey, his servants you are whom you obey, whether it be of sin unto death, or of obedience unto justice." Now in every human effort we can distinguish a beginning, a middle, and a term; and consequently the state of spiritual servitude and freedom is differentiated according to these things, namely, the beginning--to which pertains the state of beginners--the middle, to which pertains the state of the proficient--and the term, to which belongs the state of the perfect.
Reply to Objection 1. Freedom from sin results from charity which "is poured forth in our hearts by the Holy Ghost, Who is given to us" (Romans 5:5). Hence it is written (2 Corinthians 3:17): "Where the Spirit of the Lord is, there is liberty." Wherefore the same division applies to charity as to the state of those who enjoy spiritual freedom.
Reply to Objection 2. Men are said to be beginners, proficient, and perfect (so far as these terms indicate different states), not in relation to any occupation whatever, but in relation to such occupations as pertain to spiritual freedom or servitude, as stated above (Article 1).
Reply to Objection 3. As already observed (3, ad 3), nothing hinders grade and state from concurring in the same subject. For even in earthly affairs those who are free, not only belong to a different state from those who are in service, but are also of a different grade.
Source: Summa Theologica (New Advent)