Through this, God guiding us and lending a helping hand, we come to acquire the other virtues.
It is in prayer that the saints experience communion in the hidden energy of God’s holiness and inner union with it, and their intellect itself is brought through unutterable love into the presence of the Lord.
“Thou hast given gladness to my heart”, wrote the psalmist (Ps. 4:7); and the Lord Himself said that “the kingdom of heaven is within you” (cf Luke 17:21).
And what does the kingdom being within mean except that the heavenly gladness of the Spirit is clearly stamped on the virtuous soul?
For already in this life, through active communion in the Spirit, the virtuous soul receives a foretaste and a prelude of the delight, joy and spiritual gladness which the saints will enjoy in the eternal light of Christ’s kingdom.
This is something that St Paul also affirms: “He consoles us in our afflictions, so that we can console others in every affliction through the consolation with which we ourselves have been consoled by God” (2 Cor. 1:4).
And passages in the Psalms likewise hint at this active gladness and consolation of the Spirit, such as: “My heart and my flesh have rejoiced in the living God” (Ps. 84:2. LXX): and: “My soul will be filled with marrow and fatness” (Ps. 63:5).
[...] Not only does St Paul instruct us to pray without ceasing and to persist in prayer (cf. 1 Thess. 5:17; Rom. 12:12), but so also does the Lord when He says that God will vindicate those who cry out to Him day and night (cf. Luke 18:7) and counsels us to “watch and pray” (Matt. 26 : 41). We must therefore pray always and not lose heart (cf. Luke 18:1).
To put things more succinctly: he who persists in prayer has to struggle greatly and exert himself relentlessly if he is to overcome the many obstacles with which the devil tries to impede his diligence –
obstacles such as sleep, listlessness, physical torpor, distraction of thought, confusion of intellect, debility, and so on, not to mention afflictions, and also the attacks of the evil spirits that violently fight against us, opposing us and trying to prevent the soul from approaching God when it truly and ceaselessly seeks Him.
Symeon the Metaphrast (10th century?): Paraphrase of the Homilies St Makarios of Egypt, 1,18; 20. Text from G.E.H. Palmer, Philip Sherrard, and Kallistos Ware (trans. and eds.) The Philokalia: The Complete Text, vol. 3 (Faber & Faber, London & Boston: 1979).