John 7:37-38 On the last day of the feast, the great day, Jesus stood up and proclaimed, "If any one thirst, let him come to me and drink. He who believes in me, as the scripture has said, Out of his heart shall flow rivers of living water.'"
To understand this text it is necessary to remember something of the Old Testament, and in particular the Exodus, where year after year, and time after time, God caused water to pour forth from the rock, and so provided for the people of Israel, Manna that fell from heaven, and water from the rock, living water, so God provided for his people. And the people lived by faith. Manna would not keep another day, and there was no way to store enough water for the over a million people who wandered in the desert. That should have been enough, and the people should have remembered, and yet when they enter the promised land, the land flowing with milk and honey, they were quick to build storehouses and cisterns - and they began to trust in themselves, rather than to trust in God. The contrast then is between stale water, and living water.
To those in confirmation, life often seems to be filled with stale water, all those words to learn and memorize, old words, difficult words - and why? Surely school is more important, it takes up so much of our lives. And why do we need to learn so much? Others seem to learn little and yet come to this day. Why do we insist on cramming so much into your heads?
Because that's all we can do, we can teach, we can prod, we can compel you to memorize and to learn - and then we pray, that the things in your head, will get into your heart and guide your lives, that you will know the way of salvation by grace through faith and live lives of faith. We pray that you will remember, and we pray that the Holy Spirit will take the things in your head, and use them to build a strong faith in your heart.
You learned: "I believe that I cannot by my own reason or strength, believe in my Lord Jesus Christ or come to him, but the Holy Ghost has called you by the gospel, enlightened you with his gifts, sanctified and kept you in true faith". It is the Holy Ghost who takes the things in your head, and makes them a living faith in your heart. We can pray, we can teach, we can pressure, but only the Holy Ghost can create faith, sustain faith, and cause faith to grow.
We know that Jesus is the living waters, we know that having the living waters leads to eternal life. We know that he who believes and is baptized will be saved. We know that we have been called to make disciples of all nations by going and teaching and baptizing. But having this just in our heads is not enough, because we can know all these things, and not rely on them nor trust in them - which is why it is good that God has given us the gift of His Holy Spirit, who can take the things in our head, and put them into our heart, along with a living and growing faith.
So why do we need a living faith? Because by ourselves we are poor miserable sinners, spiritually blind, spiritually dead, and enemies of God. We know that the wages of sin is death. We know that all men are sinners. We know that we cannot save ourselves. We know we need a Savior. We know that Jesus died for our sins, and rose for our justification. But without faith, how can we believe that the blood of Jesus really wash away all our sins? And that is why God has given us the Holy Spirit, at our Baptism, to bring us to faith, and to keep us in faith, to create in us new hearts, and to open our hearts to the love of God which is ours in Jesus Christ.
It is by faith that we know that we are saved by grace in Christ. And yet there is so much more to the Christian life, than our salvation, or the forgiveness of sins, or eternal life. God really does have a plan for our lives, and there is a reason why the grace of God is poured out on us in overflowing measure. It is something that goes back to the great commission and show us how God is going to use us to make disciples of all nations. It is how those who believe in Christ will be seen by the world, and we see it in these words:" Out of his heart shall flow rivers of living water." Whose heart is this? The heart of every Christian, for out of our hearts the world will find the living waters which is the life and salvation which God has given us in Jesus Christ. God wants all men to be saved, we are the vessels that bring the good news of salvation unto the ends of the earth - and the Holy Ghost gives us the faith, the grace, the strength, well, he just gives us everything necessary so that God can work through us. This is the Christian life, always in Jesus name. Amen.