The Vedanta Sutras of Badarayana, Commentary by Sankara (SBE38), tr. by George Thibaut  at sacred-texts.com
8. On the passing away of the works (the soul redescends) with a remainder, according to scripture and Smriti, as it went (i.e. passing through the same stations) and not thus (i.e. in the inverse order).
Scripture states that the souls of those who perform sacrifices, and the like, rise on the road leading through smoke, and so on, to the sphere of the moon, and when they have done with the enjoyment (of the fruits of their works) again descend, 'Having dwelt there, yâvatsampâtam 2, they return again that way as they came,' &c., up to 'Those whose conduct has been good obtain some good birth, the
birth of a Brâhmana, &c.--Those whose conduct has been evil obtain the birth of a dog, &c.' (Kh. Up. V, 10, 5-7). Here it must be considered whether the souls, after having enjoyed the fruits of all their works, descend without a remainder (anusaya, of their works), or with such a remainder (of unrequited works).--The pûrvapakshin says: without such a remainder.--Why?--On account of the specification 'yâvat sampâtam.' The word sampâta here denotes the aggregate of works (karmâsaya) 1, which is so called because by it the souls pass from this world to that world for the purpose of enjoying the fruits of the works. So that the entire clause 'Having dwelt there as far as the aggregate of the works extends' indicates their works being completely requited there. The same thing is indicated by another scriptural passage, 'But when in their case that (i.e. the effect of their works) ceases' (Bri. Up. VI, 2, 16).--Well, but why should we not assume that these passages (do not mean that all works are requited there but) only indicate that the soul enjoys in the other world so long as there are works to be enjoyed there?--It is impossible to assume this, because elsewhere a reference is made to the totality of works. For the passage, Bri. Up. IV, 4, 6, 'Having obtained the end of whatever deed he does here on earth, he again returns from that world to this world to action,' intimates, by means of the comprehensive term 'whatever,' that all works done here are exhausted there.--Moreover, death has the power of manifesting those works whose fruit has not yet begun 2; the manifestation of those works not being possible previously to death because then they are obstructed by those works whose fruits have already begun. Now death must manifest alike all works whose fruits had not begun previously, because the cause being the same the effects cannot be different. Analogously a lamp which is placed at the same distance from a jar and a piece of cloth
illuminates the latter as well as the former.--Hence it follows that the souls descend without a remainder of unrequited works.
To this we reply as follows: 'On the passing away of the works with a remainder.' That means: when the aggregate of works with which the souls had risen to the moon for the purpose of the enjoyment of their fruits is, by such enjoyment, exhausted, then the body, consisting of water, which had originated in the moon for the purpose of such enjoyment, is dissolved by contact with the fire of the grief springing from the observation that the enjoyment comes to an end; just as snow and hail are melted by contact with the rays of the sun, or the hardness of ghee by contact with the heat of fire. Then, at the passing away of the works, i.e. when the works performed, such as sacrifices, &c., are, by the enjoyment of their fruits, exhausted, the souls descend with a remainder yet left.--But on what grounds is that remainder assumed?--On the ground of what is seen (Sruti) and Smriti. For scripture declares manifestly that the souls descend joined with such a remainder, 'Those whose conduct (karana) has been good will quickly attain some good birth, the birth of a Brâhmana, or a Kshattriya, or a Vaisya. But those whose conduct has been evil will quickly attain an evil birth, the birth of a dog, or a hog, or a Kândâla.' That the word karana here means the remainder (of the works) will be shown later on. Moreover, the different degrees of enjoyment which are implied in the difference of birth on the part of the living beings point, as they cannot be accidental, to the existence of such a remainder of works. For we know from scripture that good fortune as well as misfortune is caused by good and evil works. Smriti also teaches that the members of the different castes and âsramas do, in accordance with their works, at first enjoy the fruit of their works and then enter into new existences, in which they are distinguished from each other by locality, caste, family, shape, length of life, knowledge, conduct, property, pleasure, and intelligence, which doctrine implies that they descend with a remainder of their works.--Of what kind then is that so-called remainder?--
[paragraph continues] Some say that thereby we have to understand a remainder of the works which had been performed (in the previous existence) for the sake of the heavenly world, and whose fruits have (for the greater part) been enjoyed. That remainder might then be compared to the remainder of oil which sticks to the inside of a vessel previously filled with oil even after it has been emptied.--But you have no right to assume a remainder in the case of works, the fruits of which have been enjoyed already, since the adrishta (which springs from works) is opposed to the works (so as to destroy them completely 1).--This objection, we reply, is not valid, as we do not maintain that the works are completely requited (previously to the new existence).--But the souls do ascend to the sphere of the moon for the express purpose of finding there a complete requital of their works!--True; but when only a little of the effects of their works is left, they can no longer stay there. For as some courtier who has joined the king's court with all the requisites which the king's service demands is unable to remain at court any longer, when in consequence of his long stay most of his things are worn out, so that he is perhaps left with a pair of shoes and an umbrella only; so the soul, when possessing only a small particle of the effects of its works, can no longer remain in the sphere of the moon.--But all this reasoning is in fact altogether unfounded 2. For it has already been stated that, on account of (the adrishta) being opposed to the work, the continued existence of a remainder cannot be admitted in the case of works which had been performed with a view to the heavenly world, and which have been requited in the moon.--But has it not also been said above that not all the work whose fruit the heavenly world is meets with requital there?--Yes, but that statement is not defensible. For works which are performed for
the purpose of obtaining the heaven, world produce their entire heavenly fruit for the soul only as being as it stays in heaven, and if we take our stand on scripture we have no right to assume that they produce even a particle of fruit for the souls after those have again descended from heaven. That some part of the oil continues to remain in the vessel is unobjectionable because we see it, and we likewise see that some part of the courtier's equipment continues to remain with him; but that some part of those works which led the soul to heaven continues to exist, that we neither see nor are able to surmise, because it would contradict the texts declaring that the heavenly world (alone) is the fruit of the works.--That of works whose fruit is heaven, such as sacrifices and the like, no remainder continues to exist, we must necessarily acknowledge for the following reason also. If some part of those good works such as sacrifices, &c., on account of which the agents enjoyed the heavenly world, were surmised to continue in existence as a remainder, that remainder would in all cases be itself a good one, would never be of a contrary nature. But then our supposition would be in conflict with the scriptural passage which distinguishes remainders of a different kind, viz. 'Those whose conduct has been good;--those whose conduct has been evil,' &c. Hence after the fruits of that set of works which is requited in the other world have been (completely) enjoyed, the remaining other set of works whose fruits are to be enjoyed in this world constitutes the so-called anusaya with which the souls re-descend.--It was said above that we must assume the souls to descend without any such remainder, after having reached, by the enjoyment of the fruits, the end of all the works alone here below, on account of the comprehensive statement implied in the expression 'whatever.' But that assertion cannot be upheld as the existence of such a remainder has been proved. Hence we have to understand that the souls re-descend after having exhausted, by the enjoyment of its fruits, only that entire part of the works done here below whose fruit belongs to the other world and is begun to be enjoyed there.--The proof given by us of the existence of the remainder refutes at the same
time the other assertion made above, viz. that death manifests equally all works the enjoyment of whose fruits was not begun here below, and that on that account we are not entitled to draw a line between works whose fruits begin in the other world and works whose fruits begin in this world only (i.e. in a new existence on earth).--We moreover, have to ask for what reason it is maintained that death manifests (i.e. lays open and makes ready for requital those works whose fruits have not begun here below. The answer will be that in this life the operation of certain words cannot begin because it is obstructed by other works whose fruits already begin here below, that, however, that operation does begin as soon as, at the moment of death, the obstruction ceases. Well, then, if previously to death those actions whose fruits have already begun prevent other actions from beginning their operation, at the time of death also certain works of less force will be obstructed in their operation by other works of greater force, it being impossible that the fruits of works of opposite tendency should begin at the same time. For it is impossible to maintain that different deeds whose fruits must be experienced in different existences should, merely because they have this in common that their fruits have not begun (previously to death), become manifest on the occasion of one and the same death, and originate one new existence only; against this militates the fact of the definite fruits (attached to each particular work) being of contrary natures 1. Not, on the other hand, can we maintain that at the time of death some works manifest themselves while others are altogether extinguished; for that would contradict the fact that absolutely all works have their fruits. No work in fact can be extinguished except by means of expiatory actions, &c. 2 Smriti also declares that works whose operation is obstructed
by other works leading to fruits of a contrary nature last for a long time, 'Sometimes a good deed persists immovable as it were, the doer meanwhile remaining immerged in the samsâra, until at last he is released from pain.'
Moreover, if all unrequited works becoming manifest on the occasion of one and the same death were to begin one new existence only, the consequence would be that those who are born again in the heavenly world, or in hell, or as animals, could, as not entitled thereto, perform no religious works, and being thus excluded from all chance of acquiring religious merit and demerit could not enter on any new forms of existence, as all reason for the latter would be absent 1. And that would further contradict Smriti, which declares that some single actions, such as the murder of a Brâhmana, are the causes of more than one new existence. Nor can we assume, for the knowledge of the particular results springing from religious merit and demerit, any other cause than the sacred texts 2. Nor, again, does death manifest (bring about the requital of) those works whose fruit is observed to be enjoyed already here below, as, for instance, the kârîreshti, &c. 3 How then can we allow the assumption that death manifests all actions? The instance of the lamp (made use of by the pûrvapakshin) is already refuted by our having shown the relative strength of actions 4. Or else we may look on the matter as analogous to the manifestation (by a lamp) of bigger and smaller objects. For as a lamp, although equally distant from a big and a very small thing, may manifest the former only
and not the latter, so death provokes the operation of the stronger works only, not of the weaker ones, although an equal opportunity presents itself for both sets of works as hitherto unrequited.--Hence the doctrine that all works are manifested by death cannot be maintained, as it is contradicted by Sruti, Smriti, and reason alike. That the existence of a remainder of works should stand in the way of final release is a misplaced fear, as we know from Sruti that all works whatever are destroyed by perfect knowledge. It therefore is a settled conclusion that the souls re-descend with a remainder of works. They descend 'as they came' (mounted up); 'not thus,' i.e. in inverted order. We conclude that they descend 'as they came' from the fact of ether and smoke, which the text includes in the road of the fathers, being mentioned in the description of the descent also, and from the expression 'as they came.' That they follow the inverted order we conclude from night, &c., not being mentioned, and from the cloud, &c., being added.
112:2 About which term see further on.
113:1 The Comm. on Kh. Up. V, 10, 5, explains it by 'sampatanti yeneti sampâtah karmanah kshayah, yâvat sampâtam yâvat karmanah kshayah.'
113:2 Abhivyaktis ka karmanâm phalâdanâyonmukhatvam. Ân. Gi.
115:1 Bhândânusârinah snehasyâvirodhâd yuktah seshah, karma tu phalodayavirodhitvât phalam keg gâtam nashtam eveti na tasya seshasiddhir iti saṅkate nanv iti. Ân. Gi.
115:2 Ivakâro madhuroktyâ prayukto vastutas tv evakâro vivakshitah. Ân. Gi.
117:1 On which account they cannot be experienced in one and the same existence.
117:2 Works are extinguished either by expiatory ceremonies or by the knowledge of Brahman or by the full fruition of their consequences.
118:1 And in consequence of this they could never obtain final release.
118:2 We have the sacred texts only to teach us what the effects of particular good or evil actions may be.
118:3 The kârîreshti is a sacrifice offered by those who are desirous of rain.
118:4 I.e. by our having shown that death does not equally manifest all works, but that, after death has taken place, the stronger works bring about their requital while the operation of the weaker ones is retarded thereby.