Objection 1. It would seem that the active life remains after this life. For the acts of the moral virtues belong to the active life, as stated above (Article 1). But the moral virtues endure after this life according to Augustine (De Trin. xiv, 9). Therefore the active life remains after this life.
Objection 2. Further, teaching others belongs to the active life, as stated above (Article 3). But in the life to come when "we shall be like the angels," teaching will be possible: even as apparently it is in the angels of whom one "enlightens, cleanses, and perfects" [Coel. Hier. iii, viii] another, which refers to the "receiving of knowledge," according to Dionysius (Coel. Hier. vii). Therefore it would seem that the active life remains after this life.
Objection 3. Further, the more lasting a thing is in itself, the more is it able to endure after this life. But the active life is seemingly more lasting in itself: for Gregory says (Hom. v in Ezech.) that "we can remain fixed in the active life, whereas we are nowise able to maintain an attentive mind in the contemplative life." Therefore the active life is much more able than the contemplative to endure after this life.
On the contrary, Gregory says (Hom. xiv in Ezech.): "The active life ends with this world, but the contemplative life begins here, to be perfected in our heavenly home."
I answer that, As stated above (Article 1), the active life has its end in external actions: and if these be referred to the quiet of contemplation, for that very reason they belong to the contemplative life. But in the future life of the blessed the occupation of external actions will cease, and if there be any external actions at all, these will be referred to contemplation as their end. For, as Augustine says at the end of De Civitate Dei xxii, 30, "there we shall rest and we shall see, we shall see and love, we shall love and praise." And he had said before (De Civ. Dei xxii, 30) that "there God will be seen without end, loved without wearying, praised without tiring: such will be the occupation of all, the common love, the universal activity."
Reply to Objection 1. As stated above (136, 1, ad 1), the moral virtues will remain not as to those actions which are about the means, but as to the actions which are about the end. Such acts are those that conduce to the quiet of contemplation, which in the words quoted above Augustine denotes by "rest," and this rest excludes not only outward disturbances but also the inward disturbance of the passions.
Reply to Objection 2. The contemplative life, as stated above (Question 180, Article 4), consists chiefly in the contemplation of God, and as to this, one angel does not teach another, since according to Matthew 18:10, "the little ones' angels," who belong to the lower order, "always see the face of the Father"; and so, in the life to come, no man will teach another of God, but "we shall" all "see Him as He is" (1 John 3:2). This is in keeping with the saying of Jeremiah 31:34: "They shall teach no more every man his neighbor... saying: Know the Lord: for all shall know me, from the least of them even to the greatest."
But as regards things pertaining to the "dispensation of the mysteries of God," one angel teaches another by cleansing, enlightening, and perfecting him: and thus they have something of the active life so long as the world lasts, from the fact that they are occupied in administering to the creatures below them. This is signified by the fact that Jacob saw angels "ascending" the ladder--which refers to contemplation--and "descending" --which refers to action. Nevertheless, as Gregory remarks (Moral. ii, 3), "they do not wander abroad from the Divine vision, so as to be deprived of the joys of inward contemplation." Hence in them the active life does not differ from the contemplative life as it does in us for whom the works of the active life are a hindrance to contemplation.
Nor is the likeness to the angels promised to us as regards the administering to lower creatures, for this is competent to us not by reason of our natural order, as it is to the angels, but by reason of our seeing God.
Reply to Objection 3. That the durability of the active life in the present state surpasses the durability of the contemplative life arises not from any property of either life considered in itself, but from our own deficiency, since we are withheld from the heights of contemplation by the weight of the body. Hence Gregory adds (Moral. ii, 3) that "the mind through its very weakness being repelled from that immense height recoils on itself."
Source: Summa Theologica (New Advent)