As theologians wrote on the Trinity throughout Church history the centrality of the Trinity has become clearer and clearer. One such trinitarian model, the psychological model, came to the surface. Joe Rigney does a wonderful job of explaining this view of the Trinity stating that “in the Godhead, there is God in His direct existence (Father), God’s self reflection or contemplation of Himself (Son), and God’s love and delight for Himself (Holy Spirit)…there is God, God’s idea of God, and God’s love for His idea of Himself.” Before you write this view of the Trinity off as crazy, too perplexing, or even a kind of teaching taken from the psychologist Freud (which it’s not!), take note of the following passages. Colossians 1:15 says Jesus is the ‘image of the invisible God’ and Hebrews 1:3 says Jesus is the exact imprint (or representation) of God’s nature. This is why Jesus says when you’ve seen Him you really have seen the Father (John 14:7-11). Taking these passages together we understand that for all eternity God has had an image of Himself. This image is the exact imprint or representation of His nature. Because this image of God is the exact imprint of God it has pleased God to make known the glories and beauty of His own character to the world through this image, which is His Son.
What then do we make of the Holy Spirit in this description of the Trinity? The Spirit, in the above paragraph is described as ‘God’s love for His idea of Himself.’ Or to say it another way the Spirit is the very love and delight which the Father and the Son have in each other. This love that flows between the Father and the Son is deep and infinite and wonderful and exuberant. Jesus Himself speaks of this love when He mentions the ‘glory’ the Father gave Him because He loved Him before the foundation of the world in John 17:24. This love, flowing back and forth between Father and Son, is so substantial that it stands out on its own as the third Person in the Trinity, the Holy Spirit. That love then bursts out of the fellowship of the Father and Son and pours over onto us at the moment of conversion. We see this in Romans 5:5 when it says “God’s love has been poured into our hearts through the Holy Spirit who has been given to us.” It is the Spirit who is the very love of God which, from being poured into us, brings all of God’s delight in God into the soul of man.
Many theologians through history have described the Spirit like this. In Mere Christianity C.S. Lewis expressed it like this, “The union between the Father and the Son is such a live concrete thing that this union itself is also a Person. I know this is almost inconceivable, but look at it thus. You know that among human beings, when they get together in a family, or a club, or a trade union, people talk about the ‘spirit’ of that family, club, or trade union. They talk about its ‘spirit’ because the individual members, when they are together, do really develop particular ways of talking and behaving which they would not have if they were apart. It is as if a sort of communal personality came into existence. Of course, it is not a real person: it is only rather like a person. But that is just one of the differences between God and us. What grows out of the joint life of the Father and the Son is a real Person, is in fact the Third of the three Persons who are God. This Third Person is called, in technical language, the Holy Ghost or the ‘spirit’ of God. Do not be worried or surprised if you find it (or Him) rather vaguer or more shadowy in your mind than the other two. I think there is a reason why that must be so. In the Christian life you are not usually looking at Him. He is always acting through you. If you think of the Father as something ‘out there’, in front of you, and of the Son as someone standing at your side, helping you to pray, trying to turn you into another son, then you have to think of the third Person as something inside you, or behind you…God is love, and that love works through men-especially through the whole community of Christians. But this spirit of love is, from all eternity, a love going on between the Father and the Son.”
Jonathan Edwards said it like this years before Lewis did in his own Puritan manner. “The Godhead being thus begotten by God’s loving an idea of Himself and shewing forth in a distinct subsistence or person in that idea, there proceeds a most pure act, and an infinitely holy and sacred energy arises between the Father and Son in mutually loving and delighting in each other, for their love and joy is mutual, Proverbs 8:30 – “I was daily His delight, rejoicing always before Him.” This is the eternal and most perfect and essential act of the divine nature, wherein the Godhead acts to an infinite degree and in the most perfect manner possible. The Deity becomes all act, the Divine essence itself flows out and is, as it were, breathed forth in love and joy. So that the Godhead therein stands forth in yet another manner of subsistence, and there proceeds the third person in the Trinity, the Holy Spirit, viz. the deity in act, for there is no other act but the act of the will.”
Edwards went on to conclude the following about the Trinity as a whole, “The Father is the deity subsisting in the prime, unoriginated and most absolute manner, or the deity in its direct existence. The Son is the deity generated by God’s understanding, or having an idea of Himself and subsisting in that idea. The Holy Ghost is the deity subsisting in act, or the divine essence flowing out and breathed forth in God’s infinite love to and delight in Himself. And I believe the whole Divine essence does truly and distinctly subsist both in the Divine idea and Divine love, and that each of them are distinct persons.”
Since the Holy Spirit is the love which flows out from and breathes forth between the Father and the Son, see the beauty in Jesus’ words in John 15:11, “These things I have spoken to you that My joy may be in you, and that your joy may be full.” In context ‘these things’ refers to all Jesus taught in 15:1-10, but the substance of Edwards and Lewis and all we’ve mentioned before fits within this statement as well. The reason our joy is full is because the joy Jesus gives to and places within us, is none other than the Holy Spirit Himself. So be encouraged, and behold our God. Look at the Father: infinite in His wisdom, wondrous in His majesty, and perfect in His purpose. Look at the Son: humble in His incarnation and death, exalted in His resurrection and ascension, and ever faithful in His intercession for us. And look at the Spirit enlightening in His illumination, consoling in His comfort, strengthening in His sanctifying support.
 This model is described in the writings of Augustine, Jonathan Edwards, and even shows up in C.S. Lewis on a few occasions, I first read of it in Joe Rigney’s book The Things of Earth, page 37-39.
 Joe Rigney, The Things of Earth, page 37
 Lewis, Mere Christianity, page 175-176.
 Edwards, An Essay on the Trinity, page 108.
 Edwards, An Essay on the Trinity, page 118.