If our human nature is not kept pure or else restored to its original purity by the Holy Spirit, it cannot become one body and one spirit in Christ, either in this life or in the harmonious order of the life to come.

For the all-embracing and unifying power of the Spirit does not complete the new garment of grace by sewing on to it a patch taken from the old garment of the passions (cf.Matt. 9:16).

Every person who has been renewed in the Spirit and has preserved this gift will be transformed and embodied in Christ, experiencing ineffably the supernatural state of deification.

But he will not hereafter be one with Christ or be engrafted into His body unless in this life he has come to share in divine grace and has embodied spiritual knowledge and truth.

The kingdom of heaven is like the tabernacle which was built by God, and which He disclosed to Moses as a pattern (cf. Exod. 25:40); for it too has an outer and an inner sanctuary.

Into the first will enter all who are priests of grace. But into the second – which is noetic – will enter only those who in this life have attained the divine darkness of theological wisdom and there as true hierarchs have celebrated the triadic liturgy, entering into the tabernacle that Jesus Himself has set up, where He acts as their consecrator and chief Hierarch before the Trinity, and illumines them ever more richly with His own splendor.

By ‘many dwelling-places’ (John14:2) the Savior meant the differing stages of spiritual ascent and states of  development in the other world; for although the kingdom of heaven is one, there are many different levels within it.

That is to say, there is place for both heavenly and earthy men (cf.1Cor.15:48) according to their virtue, their knowledge and the degree of deification that they have attained.

‘For there is one glory of the sun, and another glory of the moon, and another glory of the stars, for one star differs from another star in glory’(1Cor. 15:41); and yet all of them shine in a single divine firmament.

You partake of angelic life and attain an incorruptible and hence almost bodiless state when you have cleansed your intellect through tears, have through the power of the Spirit resurrected your soul even in this life, and with the help of the Logos have made your flesh – your natural human form of clay – a resplendent and fiery image of divine beauty.

Gregory of Sinai (1260s–1346): On Commandments and Doctrines, chs 41-45, Text from G.E.H. Palmer, Philip Sherrard, and Kallistos Ware (trans. and eds.) The Philokalia: The Complete Text, vol. 4 (Faber & Faber, London & Boston: 1979ff), pp. 220-221.