CCC 671 Though already present in his Church, Christ’s reign is nevertheless yet to be fulfilled “with power and great glory” by the King’s return to earth.1 This reign is still under attack by the evil powers, even though they have been defeated definitively by Christ’s Passover.2 Until everything is subject to him, “until there be realized new heavens and a new earth in which justice dwells, the pilgrim Church, in her sacraments and institutions, which belong to this present age, carries the mark of this world which will pass, and she herself takes her place among the creatures which groan and travail yet and await the revelation of the sons of God.”3 That is why Christians pray, above all in the Eucharist, to hasten Christ’s return by saying to him:4 Marana tha! “Our Lord, come!”5

CCC 697 Cloud and light. These two images occur together in the manifestations of the Holy Spirit. In the theophanies of the Old Testament, the cloud, now obscure, now luminous, reveals the living and saving God, while veiling the transcendence of his glory – with Moses on Mount Sinai,6 at the tent of meeting,7 and during the wandering in the desert,8 and with Solomon at the dedication of the Temple.9 In the Holy Spirit, Christ fulfills these figures. The Spirit comes upon the Virgin Mary and “overshadows” her, so that she might conceive and give birth to Jesus.10 On the mountain of Transfiguration, the Spirit in the “cloud came and overshadowed” Jesus, Moses and Elijah, Peter, James and John, and “a voice came out of the cloud, saying, ‘This is my Son, my Chosen; listen to him!’”11 Finally, the cloud took Jesus out of the sight of the disciples on the day of his ascension and will reveal him as Son of man in glory on the day of his final coming.12

CCC 2612 In Jesus “the Kingdom of God is at hand.”13 He calls his hearers to conversion and faith, but also to watchfulness. In prayer the disciple keeps watch, attentive to Him Who Is and Him Who Comes, in memory of his first coming in the lowliness of the flesh, and in the hope of his second coming in glory.14 In communion with their Master, the disciples’ prayer is a battle; only by keeping watch in prayer can one avoid falling into temptation.15

1 Lk 21:27; cf. Mt 25:31.
2 Cf. 2 Th 2:7.
3 LG 48 # 3; cf. 2 Pt 3:13; Rom 8:19-22; I Cor 15:28.
4 Cf. I Cor 11:26; 2 Pt 3:11-12.
5 1 Cor 16:22; Rev 22:17,20.
6 Cf. Ex 24:15-18.
7 Cf. Ex 33:9-10.
8 Cf. Ex 40:36-38; 1 Cor 10:1-2.
9 Cf. 1 Kings 8:10-12.
10 Lk 1:35.
11 Lk 9:34-35.
12 Cf. Acts 1:9; cf. Lk 21:27.
13 Mk 1:15.
14 Cf. Mk 13; Lk 21:34-36.
15 Cf. Lk 22:40, 46.