...It is thus fitting that, anger and desire repudiated, we should next invoke the rule of the kingdom of God the Father with the words ‘Thy kingdom come’ (Matt. 6:l0), that is, ‘May the Holy Spirit come’; for, having put away these things, we are now made into a temple for God through the Holy Spirit by the teaching and practice of gentleness. ‘For on whom shall I rest,’ says Scripture, ‘but on him who is gentle and humble, and trembles at my words?’ (cf. Isa, 66:2). It is dear from this that the kingdom of God the Father belongs to the humble and the gentle. For ‘blessed are the gentle, for they will inherit the earth’ (Matt. 5:5). It is not this physical earth, which by nature occupies a middle place in the universe, that God promises as an inheritance for those who love Him - not, at least, if He is speaking truly when He says, ‘In the resurrection they neither marry nor are given in. marriage, but are as the angels in heaven’ (Matt. 22:30), and ‘Come, you whom my Father has blessed, inherit the kingdom prepared for you from the foundation of the world’ (Matt. 25:34), and elsewhere again to someone else who has striven with goodwill, ‘Enter into the joy of your Lord’ (Matt. 25:21). And after the Lord St Paul also says, ‘The trumpet will sound and first the dead in Christ will rise up incorrupt; then we who are alive and remain will be caught up with them in the clouds to meet the Lord in the air; and so we shall be with the Lord for ever’ (cf. 1 Thess. 4:16-17).
Since these things have been promised to those who love the Lord, what man prompted by intelligence and wishing to serve it would ever say, from a literal reading of Scripture alone, that heaven, and the kingdom prepared from the foundation of the world, and the mystically hidden joy of the Lord, and the perpetual dwelling with the Lord enjoyed by the saints, are to be identified with the earth? In this text (Matt. 5:5) I trink that the word ‘earth’ signifies the resolution and strength of the inner stability, immovably rooted in goodness, that is possessed by gentle, people. This state of stability exists eternally with the Lord, contains unfailing joy, enables the gentle to attain the kingdom prepared from the beginning, and has its station and dignity in heaven. It also permits the gentle to inherit the principle of virtue, as if virtue were the earth that occupies a middle place in the universe. For the gentle person holds a middle position between honor and obloquy, and remains dispassionate, neither puffed up by the first nor cast down by the second. For the intelligence is by nature superior to both praise and blame; and so, when it has put away the sensual desire, it is no longer troubled by either the one or the other, having anchored the whole power of the soul in divine and unassailable liberty. The Lord, wanting to impart this liberty to His disciples says, ‘Take my yoke upon you and learn from Me; for I am gentle and humble in heart; and you will find rest for your souls’ (Matt. 11:29). He calls the rule of the divine kingdom ‘rest’ because it confers on those worthy of it a lordship free from all servitude... - St Maximos the Confessor, "On the Lord’s Prayer"