Now when the king was settled in his house, and the Lord had given him rest from all his enemies around him, the king said to the prophet Nathan, “See now, I am living in a house of cedar, but the ark of God stays in a tent.” Nathan said to the king, “Go, do all that you have in mind; for the Lord is with you.”
But that same night the word of the Lord came to Nathan: Go and tell my servant David: Thus says the Lord: Are you the one to build me a house to live in?
I took you from the pasture, from following the sheep to be prince over my people Israel; and I have been with you wherever you went, and have cut off all your enemies from before you; and I will make for you a great name, like the name of the great ones of the earth. And I will appoint a place for my people Israel and will plant them, so that they may live in their own place, and be disturbed no more; and evildoers shall afflict them no more, as formerly, from the time that I appointed judges over my people Israel; and I will give you rest from all your enemies. Moreover the Lord declares to you that the Lord will make you a house. When your days are fulfilled and you lie down with your ancestors, I will raise up your offspring after you, who shall come forth from your body, and I will establish his kingdom.
I will be a father to him, and he shall be a son to me. Your house and your kingdom shall be made sure forever before me; your throne shall be established forever.
This breathing of the air is an ability that the soul states God will give her there in the communication of the Holy Spirit. By his divine breath-like spiration, the Holy Spirit elevates the soul sublimely and informs her and makes her capable of breathing in God the same spiration of love that the Father breathes in the Son and the Son in the Father. This spiration of love is the Holy Spirit himself, who in the Father and the Son breathes out to her in this transformation in order to unite her to himself. There would not be a true and total transformation if the soul were not transformed in the three Persons of the Most Holy Trinity in an open and manifest degree.
No knowledge or power can describe how this happens, unless by explaining how the Son of God attained and merited such a high state for us, the power to be children of God, as St. John says (Jn. 1:12). Thus the Son asked of the Father in St. John’s Gospel: Father, I desire that where I am those you have given me may also be with me, that they may see the glory you have given me (Jn. 17:24), that is, that they may perform in us by participation the same work that I do by nature; that is, breathe the Holy Spirit. And he adds: I do not ask, Father, only for those present, but for those also who will believe in me through their doctrine; that all of them may be one as you, Father, in me and I in you, that thus they be one in us. The glory which you have given me I have given them that they may be one as we are one, I in them and you in me; that they may be perfect in one; that the world may know that you have sent me and loved them as you have loved me (Jn. 17:20-23). The Father loves them by communicating to them the same love he communicates to the Son, though not naturally as to the Son but, as we said, through unity and transformation of love. It should not be thought that the Son desires here to ask the Father that the saints be one with him essentially and naturally as the Son is with the Father, but that they may be so through the union of love, just as the Father and the Son are one in unity of love.
Accordingly, souls possess the same goods by participation that the Son possesses by nature. As a result they are truly gods by participation, equals and companions of God.
Saint John of the Cross
The Spiritual Canticle, Stanza 39.3,5–6
New Revised Standard Version Bible: Catholic Edition scripture references provided by biblegateway.com
John of the Cross, St. 1991, The Collected Works of St. John of the Cross, Revised Edition, translated from the Spanish by Kavanaugh, K and Rodriguez, O with revisions and introductions by Kavanaugh, K, ICS Publications, Washington DC.