There has been given to us the renewing Spirit, that is, the Holy, the occasion of everlasting life after that Christ was glorified, i.e., after the Resurrection.
Having burst the bonds of death and appeared superior to all corruption, He lived again having our whole nature in Himself, in that He was Man and One of us.
And if you investigate the reason why the pouring forth of the Spirit took place not before the resurrection but after it, you will hear in reply, Christ became then the firstfruits of the renewed nature.
Making no account of the bands of death He lived again as we have just now said. How then should those be quickened before the Firstfruit who come after the Firstfruit?
The plant will not shoot up from the earth unless it is surely sprung from its own root (for thence is the beginning of its growth).
So also it was impossible that we, who have as our root unto incorruption our Lord Jesus Christ, should be seen springing up before our root.
But, shewing that the time of the Descent of the Spirit upon us was now come after the revival from the dead, He breathed on His disciples, saying, Receive ye the Holy Ghost.
For then was the time of the renewal indeed at the doors, yea rather within the doors. And let the searcher after learning again see whether what we say on these things too be not true.
For in the beginning, as the Spirit-clad Moses told us, the Creator of all, taking dust of the ground and having formed man, breathed upon his face the breath of life.
And what is the breath of life, save surely the Spirit of Christ Who says, I am the Resurrection and the Life?
But since the Spirit which is able to gather us and to form us unto the Divine Impress fled away from human nature [i.e. after Adam’s sin], the Saviour gives us the Spirit anew, bringing us again unto that ancient dignity and reforming us unto His own Image.
For therefore does Paul too say…, Little children of whom I travail in birth again until Christ be formed in you.
[…] In the holy Prophets there was a certain rich shining-upon and torch-illumination from the Spirit, mighty to lead them to the apprehension of things to come and the knowledge of things hidden.
But in those who believe on Christ, we are confident that not merely torch-illumination from the Spirit but the Spirit Himself dwells and has His habitation.
Whence rightly are we called temples too of God, though no one of the holy Prophets was ever called a Divine Temple.
Cyril of Alexandria (c. 376-444): Commentary on John, Book 5 (on John 7:39); slightly adapted.