Nicene and Post-Nicene Fathers, Ser. II, Vol. XI:
The Works of John Cassian.: Chapter XIII. The answer concerning the direction of the heart towards and concerning the kingdom of God and the kingdom of the devil.

Chapter XIII.

The answer concerning the direction of the heart towards and concerning the kingdom of God and the kingdom of the devil.

Moses. To cling to God continually, and as you say inseparably to hold fast to meditation on Him, is impossible for a man while still in this weak flesh of ours. But we ought to be aware on what we should have the purpose of our mind fixed, and to what goal we should ever recall the gaze of our soul: and when the mind can secure this it may rejoice; and grieve and sigh when it is withdrawn from this, and as often as it discovers itself to have fallen away from gazing on Him, it should admit that it has lapsed from the highest good, considering that even a momentary departure from gazing on Christ is fornication. And when our gaze has wandered ever so little from Him, let us turn the eyes of the soul back to Him, and recall our mental gaze as in a perfectly straight direction. For everything depends on the inward frame of mind, and when the devil has been expelled from this, and sins no longer reign in it, it follows that the kingdom of God is founded in us, as the Evangelist says “The kingdom of God cometh not with observation, nor shall men say Lo here, or lo there: for verily I say unto you that the kingdom of God is within you.” 1100 But nothing else can be “within you,” but knowledge or ignorance of truth, and delight either in vice or in virtue, through which we prepare a kingdom for the devil or for Christ in our heart: and of this kingdom the Apostle describes the character, when he says “For the kingdom of God is not meat and drink, but righteousness and peace and joy in the Holy Ghost.” 1101 And so if the kingdom of God is within us, and the actual kingdom of God is righteousness and peace and joy, then the man who abides in these is most certainly in the kingdom of God, and on the contrary those who live in unrighteousness, and discord, and the sorrow that worketh death, have their place in the kingdom of the devil, and in hell and death. For by these tokens the kingdom of God and the kingdom of the devil are distinguished: and in truth if lifting up our mental gaze on high we would consider that state in which the heavenly powers live on high, who are truly in the kingdom of God, what should we imagine it to be except perpetual and lasting joy? For what is so specially peculiar and appropriate to true blessedness as constant calm and eternal joy? And that you may be quite sure that this, which we say, is really so, not on my own authority but on that of the Lord, hear how very clearly He describes the character and condition of that world: “Behold,” says He, “I create new heavens and a new earth: and the former things shall not be remembered nor come into mind. But ye shall be glad and rejoice forever in that which I create.” 1102 And again “joy and gladness shall be found therein: thanksgiving and the voice of praise, and there shall be month after month, and Sabbath after Sabbath.” 1103 And again: “they shall obtain joy and gladness; and sorrow and sighing shall flee away.” 1104 And if you want to know more definitely about that life and the city of the saints, hear what the voice of the Lord proclaims to the heavenly Jerusalem herself: “I will make,” says He, “thine officers peace and thine overseers righteousness. Violence shall no more be heard in thy land, desolation nor destruction within thy borders. And salvation shall take possession of thy walls, and praise of thy gates. The sun shall be no more thy light by day, neither shall the brightness of the moon give light to thee: but the Lord shall be p. 301 thine everlasting light, and thy God thy glory. Thy sun shall no more go down, neither shall thy moon withdraw itself: but the Lord shall be thine everlasting light, and the days of thy mourning shall be ended:” 1105 and therefore the holy Apostle does not say generally or without qualification that every joy is the kingdom of God, but markedly and emphatically that joy alone which is “in the Holy Ghost.” 1106 For he was perfectly aware of another detestable joy, of which we hear “the world shall rejoice,” 1107 and “woe unto you that laugh, for ye shall mourn.” 1108 In fact the kingdom of heaven must be taken in a threefold sense, either that the heavens shall reign, i.e., the saints over other things subdued, according to this text, “Be thou over five cities, and thou over ten;” 1109 and this which is said to the disciples: “Ye shall sit upon twelve thrones judging the twelve tribes of Israel:” 1110 or that the heavens themselves shall begin to be reigned over by Christ, when “all things are subdued unto Him,” and God begins to be “all in all:” 1111 or else that the saints shall reign in heaven with the Lord.

Footnotes

S. Luke 17:20, 21.

Rom. xiv. 17.

Isa. 65:17, 18.

Isa. 51:3, Isa. 66:23.

Is. xxxv. 10.

Is. lx. 17-20.

Cf. Rom. xiv. 17.

S. John xvi. 20.

S. Luke vi. 25.

S. Luke 19:17, 19.

S. Matt. xix. 28.

1 Cor. xv. 28.