Objection 1. It would seem that we should not distinguish so many abodes. For after death, just as abodes are due to souls on account of sin, so are they due on account of merit. Now there is only one abode due on account of merit, namely paradise. Therefore neither should there be more than one abode due on account of sin, namely hell.
Objection 2. Further, abodes are appointed to souls after death on account of merits or demerits. Now there is one place where they merit or demerit. Therefore only one abode should be assigned to them after death.
Objection 3. Further, the places of punishment should correspond to the sins. Now there are only three kinds of sin, namely original, venial, and mortal. Therefore there should only be three penal abodes.
Objection 4. On the other hand, it would seem that there should be many more than those assigned. For this darksome air is the prison house of the demons (2 Peter 2:17), and yet it is not reckoned among the five abodes which are mentioned by certain authors. Therefore there are more than five abodes.
Objection 5. Further, the earthly paradise is distinct from the heavenly paradise. Now some were borne away to the earthly paradise after this state of life, as is related of Enoch and Elias. Since then the earthly paradise is not counted among the five abodes, it would seem that there are more than five.
Objection 6. Further, some penal place should correspond to each state of sinners. Now if we suppose a person to die in original sin who has committed only venial sins, none of the assigned abodes will be befitting to him. For it is clear that he would not be in heaven, since he would be without grace, and for the same reason neither would he be in the limbo of the Fathers; nor again, would he be in the limbo of children, since there is no sensible punishment there, which is due to such a person by reason of venial sin: nor would he be in purgatory, where there is none but temporal punishment, whereas everlasting punishment is due to him: nor would he be in the hell of the damned, since he is not guilty of actual mortal sin. Therefore a sixth abode should be assigned.
Objection 7. Further, rewards and punishments vary in quantity according to the differences of sins and merits. Now the degrees of merit and sin are infinite. Therefore we should distinguish an infinite number of abodes, in which souls are punished or rewarded after death.
Objection 8. Further, souls are sometimes punished in the places where they sinned, as Gregory states (Dial. iv, 55). But they sinned in the place which we inhabit. Therefore this place should be reckoned among the abodes, especially since some are punished for their sins in this world, as the Master said above (Sent. iv, D, 21).
Objection 9. Further, just as some die in a state of grace and have some venial sins for which they deserve punishment, so some die in mortal sin and have some good for which they would deserve a reward. Now to those who die in grace with venial sins an abode is assigned where they are punished ere they receive their reward, which abode is purgatory. Therefore, on the other hand, there should be equally an abode for those who die in mortal sin together with some good works.
Objection 10. Further, just as the Fathers were delayed from obtaining full glory of the soul before Christ's coming, so are they now detained from receiving the glory of the body. Therefore as we distinguish an abode of the saints before the coming of Christ from the one where they are received now, so ought we to distinguish the one in which they are received now from the one where they will be received after the resurrection.
I answer that, The abodes of souls are distinguished according to the souls' various states. Now the soul united to a mortal body is in the state of meriting, while the soul separated from the body is in the state of receiving good or evil for its merits; so that after death it is either in the state of receiving its final reward, or in the state of being hindered from receiving it. If it is in the state of receiving its final retribution, this happens in two ways: either in the respect of good, and then it is paradise; or in respect of evil, and thus as regards actual sin it is hell, and as regards original sin it is the limbo of children. On the other hand, if it be in the state where it is hindered from receiving its final reward, this is either on account of a defect of the person, and thus we have purgatory where souls are detained from receiving their reward at once on account of the sins they have committed, or else it is on account of a defect of nature, and thus we have the limbo of the Fathers, where the Fathers were detained from obtaining glory on account of the guilt of human nature which could not yet be expiated.
Reply to Objection 1. Good happens in one way, but evil in many ways, according to Dionysius (Div. Nom. iv) and the Philosopher (Ethic. ii, 6): wherefore it is not unfitting if there be one place of blissful reward and several places of punishment.
Reply to Objection 2. The state of meriting and demeriting is one state, since the same person is able to merit and demerit: wherefore it is fitting that one place should be assigned to all: whereas of those who receive according to their merits there are various states, and consequently the comparison fails.
Reply to Objection 3. One may be punished in two ways for original sin, as stated above, either in reference to the person, or in reference to nature only. Consequently there is a twofold limbo corresponding to that sin.
Reply to Objection 4. This darksome air is assigned to the demons, not as the place where they receive retribution for their merits, but as a place befitting their office, in so far as they are appointed to try us. Hence it is not reckoned among the abodes of which we are treating now: since hell fire is assigned to them in the first place (Matthew 25).
Reply to Objection 5. The earthly paradise belongs to the state of the wayfarer rather than to the state of those who receive for their merits; and consequently it is not reckoned among the abodes whereof we are treating now.
Reply to Objection 6. This supposition is impossible [Cf. I-II, 89, 6]. If, however, it were possible, such a one would be punished in hell eternally: for it is accidental to venial sin that it be punished temporally in purgatory, through its having grace annexed to it: wherefore if it be annexed to a mortal sin, which is without grace, it will be punished eternally in hell. And since this one who dies in original sin has a venial sin without grace, it is not unfitting to suppose that he be punished eternally.
Reply to Objection 7. Diversity of degrees in punishments or rewards does not diversify the state, and it is according to the diversity of state that we distinguish various abodes. Hence the argument does not prove.
Reply to Objection 8. Although separated souls are sometimes punished in the place where we dwell, it does not follow that this is their proper place of punishment: but this is done for our instruction, that seeing their punishment we may be deterred from sin. That souls while yet in the flesh are punished here for their sins has nothing to do with the question, because a punishment of this kind does not place a man outside the state of meriting or demeriting: whereas we are treating now of the abodes to which souls are assigned after the state of merit or demerit.
Reply to Objection 9. It is impossible for evil to be pure and without the admixture of good, just as the supreme good is without any admixture of evil. Consequently those who are to be conveyed to beatitude which is a supreme good must be cleansed of all evil. wherefore there must needs be a place where such persons are cleansed if they go hence without being perfectly clean. But those who will be thrust into hell will not be free from all good: and consequently the comparison fails, since those who are in hell can receive the reward of their goods, in so far as their past goods avail for the mitigation of their punishment.
Reply to Objection 10. The essential reward consists in the glory of the soul, but the body's glory, since it overflows from the soul, is entirely founded as it were on the soul: and consequently lack of the soul's glory causes a difference of state, whereas lack of the body's glory does not. For this reason, too, the same place, namely the empyrean, is assigned to the holy souls separated from their bodies and united to glorious bodies: whereas the same place was not assigned to the souls of the Fathers both before and after the glorification of souls.
Source: Summa Theologica (New Advent)