Today is a peculiar day in the church’s calendar. It is a day of special importance, but it is markedly different from say Christmas or Easter. Today is not about remembering a particular event in the life and ministry of our Lord but it is about focusing on the nature of our God Himself. It is Trinity Sunday, and we take a moment to renew our confession that our God, the God Christians worship, the God who has called us together in the first place, the God in whom we trust and live and move and have our being, that God is triune in nature. He is one God: Father, Son, and Holy Spirit. To help us think through such an incredible thing as the nature of a triune God, we dig out and dust off the old Athanasian Creed. This, the last of the great ecumenical creeds of the Church, engages us with its rhythmic style, confessing the truth of the nature of our God. “That we worship one God in Trinity, and Trinity in Unity; neither confusing the Persons, nor dividing the substance.”

Now, our rare use of this creed causes it to sound strange and archaic to our ears, and perhaps that is reason enough to use it even more. It is full of specific and even technical language which separates the faithful teaching about our God from all the false teachers who came about and continue to plague the Church. It is an attempt, and I think a particularly good one, to put into succinct words just how the work of God is described in the pages of Scripture. But if you take a good look at the Creed, you will notice only the first half of it deals specifically with the Holy Trinity. The whole second half of the Creed is focused on answering the questions of who Jesus is. Again, using precise and technical language it discusses the two natures in Christ, the reality that our Savior is both true God and true man. As we confess in the Creed, “He is God, begotten from the substance of the Father before all ages; and He is man, born from the substance of His mother in this age: perfect God and perfect man, composed of a rational soul and human flesh; equal to the Father with respect to His divinity, less than the Father with respect to His humanity.”

In a way, this is the Church’s attempt to faithfully answer the question that the Pharisees posed to our Lord when they said, “Who do you make yourself out to be?” And the answer matters, not just to clarify what we confess regarding our Lord, but it matters because it will say something about who you are as well. Our text for today from John 8 drops us right into the middle of an intense argument between our Lord and the religious leaders of His day. They say, “Are we not right in saying you are a Samaritan and have a demon?” And you might be thinking, man that is a bit rough. What did He do to deserve the attack? But if you were to read a little before our text, you find Jesus has just said to them, “Why do you not understand what I say? It is because you cannot bear to hear My word. You are of your father the devil, and your will is to do your father’s desires. He was a murderer from the beginning, and does not stand in the truth, because there is no truth in him.” So, there is a line drawn in the sand. People are taking sides, and it all hinges on just who Jesus really is. And to speak about the identity of our Lord is to speak about the totality of God Himself.

To confess that we worship the Holy Trinity, that we have one God in three persons, may seem strange and mysterious. It may seem a bit of a stretch of the imagination, or just a fun but inconsequential academic exorcise. But when you step back and look at the teaching of the Holy Trinity all it turns out to be is a description of a God who is at work. The only reason we get this whole language of Father, Son, and Holy Spirit is because this is how our God describes Himself working in this world. From the creation of the cosmos to the gift of life, to the revelation of truth, to the promise of restoration, and living in righteousness it is what He says about Himself. God discloses Himself as a Father, a Son, and a Spirit who works through history, through the physical things of our world, through the Church and the saints of God to seek and save the lost, to proclaim salvation to you. A triune God is a God who actively engages His creation.

To confess our God is a God who is at work is to confess He has something to say to you, that He will impact your life, that you do not roll on unnoticed and forgotten in this age. The fact you are here is a testimony of how God has indeed gotten ahold of you. He has challenged you, emptied you out to the point you could no longer ignore Him. He declares to you He is the creator of the heavens and the earth. He has established the whole of order of the cosmos and His Law is given as a standard for living as His own. His Spirit is sent into your hearts to awaken your faith to hear His Word and take it to heart. So, you are measured and weighed out by your God. You are examined, sifted, and found over and again to be wanting. You fall short of the glory demanded of His creation and the work of God in our age exposes all of this. You have transgressed the laws of the creator of all things and there is now a debt which must be paid, and the payment is death.

But again, our God is a God at work, one God, in three persons. And there is a Savior to whom we can and must run. There is One who will give hope and life to repentant sinners. The Son of God comes to do what you and I could not do. He comes to live the perfect life, to be faithful to every point of the Law of the Father, to be truly just, holy, and righteous in all things. Then in that perfection, He does the most shocking thing. He takes the sins you have done, the transgressions you have committed, and He declares they are His. He dares death to come after Him, to reach out and claim the One whose sins are not His own but yours. With such work He promises life and salvation. With such action God proclaims life to all who believe in Him. The Father, Son, and Holy Spirit are all at work for you, to open the gates of eternal life to you, to welcome you.

So, Jesus replies to His detractors and says, “I do not have a demon, but I honor My Father, and you dishonor Me. Yet I do not seek My own glory; there is One who seeks it, and He is the judge. Truly, truly, I say to you, if anyone keeps My word, he will never see death.” God is at work and the Word He declares through the Son is the key to eternal life. This Word speaks of what Christ has done, the Word which declares the salvation accomplished by the life, death, and resurrection of Jesus. That Word the Spirit opens your ears to hear is the very means by which you will live. Jesus is the key, the answer, the only way to eternal life. His opponents get this, and they challenge Him saying, “Who does He make Himself out to be? Does He think He is greater than our father Abraham?”

And this is where our Lord drops the hammer. If they thought He was being problematic when He accused them of having Satan as their father, He now discloses something about Himself that fundamentally challenges everything they believe. He says to them, “Your father Abraham rejoiced that he would see My day. He saw it and was glad.” Abraham believed in the promises of God. He believed, and it was counted to him as righteousness. And the promises of God are centered in deliverance, in forgiveness, in the gift of life. Again, they are perplexed. Just who is this? Who is Jesus? How could He have seen Abraham? And Jesus said to them, “Truly, truly, I say to you, before Abraham was, I am.”

This is God of God, Light of Light, very God of very God, begotten not made. This is the work of the Holy Trinity and the only means of salvation. What Abraham rejoiced in is what you rejoice in. Our God is a God at work, a God who has found you, called you by name, clothed you in His righteous garments, and declared in the heavenly courts that you are forgiven all of your sins. To keep His Word is to trust in the promises He proclaims. To keep His Word is to believe in what He says about you as our father Abraham did. And He says to you this day that you are loved, your sins are forgiven, and you will live for all eternity.