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Deep Certainty

To know Jesus is to know, for certain, eternal life.
This sermon is part of the sermon series "Living Deep". See series.

How do you feel about the future? What kind of world will our children and grandchildren, grow up in? What can we count on to give us any kind of confidence as we look to the future?

We come this morning to the final installment in John's letter. It's a letter that was written a long time ago to the church in a place called Ephesus, but we've been finding that it speaks quite powerfully to our own lives and churches, here in the 21st century. It's a compelling letter, strikingly simple, but it raises all kinds of questions, as we've been learning from our weekly letter writers.

There's Victor, troubled by the fact that he keeps losing his temper with his wife. Is there something wrong with him, or his faith? And Albert, an older gentleman who's been following Christ his whole life but still isn't always the man he wants to be. Will he ever be that man? Liz is a teenager. She's happy with her faith but wonders about all the other faiths out there. Is there one truth, or many? A 20-something named Angie is enjoying her first taste of "the good life"—money, career, freedom—but wonders if a Christian can live with one foot in the world and the other in God's kingdom. There's Marissa, a good wife, and Neil, a straight-arrow executive. They're doing all the things Christians are supposed to do—reading the Bible, going to church—but where's the joy, they wonder, and the impact? Are they missing something? And this morning we heard from Nina, who speaks for all of them, and maybe even for us, when she says she wants to believe, but sometimes she needs help believing. Is there anything we can be certain of, she asks, in a world that's so unpredictable and frightening?

Fortunately, John wrote his letter to answer questions like these from people like us. So let's open one more time to the book of 1 John, as we focus on the closing paragraphs of chapter 5. We'll pick up the reading at 5:11-13: "And this is the testimony: God has given us eternal life, and this life is in his Son. He who has the Son has life; he who does not have the Son does not have life. I write these things to you who believe in the name of the Son of God so that you may know that you have eternal life."

A culture of doubt

Let's remember the situation these original readers were in. They were 2nd or 3rd generation believers, 50 years removed from Jesus of Nazareth. A lot had happened in those years. Jerusalem had fallen to the Romans, who desecrated the temple, then destroyed it. The world was now under the thumb of a pagan empire. Jews had been scattered among the nations, and the fledgling Christian church was misunderstood and persecuted. Most of the apostles had been martyred for their faith, and there were only a few remaining eyewitnesses to the life and death of Jesus.

And now, false teachers had infiltrated the church, and were calling into question the central tenets of their faith. Jesus didn't really have a body, they said, he just appeared to. Faith isn't what matters, they said, it's enlightenment—secret truths and mystical experiences. No one can be sure of their standing before God, they said, divine reality is far too mysterious for that. Many believers were beginning to doubt their faith. They were wondering if it was really true, if they were really Christians, and if they could count on anything as the world seemed to be falling apart around them.

And 2,000 years later, we are prone to the very same doubts. There's not a believer here who hasn't questioned his or her faith at some point. Maybe you made a commitment to Christ some time ago, but it seems to have little meaning to you anymore. Maybe you've been struggling with sin in your life, and you're wondering how you could be a real Christian and still think or do some of those things. It could be you've read a book recently or heard a speaker or took a class that has caused you to question your faith on an intellectual level. You look at other Christians, and they seem to have such passion and joy and power, and you wonder what's wrong with your faith. Is it real? Are you really saved?

And while Christians have always struggled with doubt, in our post-modern, 21st century world, it seems harder than ever to be sure of anything. A few years ago, Drew Faust became president of Harvard University. In her inaugural speech, she called attention to the crest of the college, which bears the one-word motto of the school, Veritas, which is Latin for truth. She pointed out that the motto originally affirmed the school's quest for eternal truths and unassailable realities. But then she went on to announce a new understanding of that quest: "Truth is an aspiration," she said, "not a possession. In this we … challenge those who would embrace such certainties. We must commit ourselves to the uncomfortable position of doubt." When the most-highly regarded intellectual institution in the world is telling us we can't really know anything, for certain, it feels as though the very ground beneath our feet is giving way, and there's no place to stand. If the folks at Harvard don't know anything, what hope is there for the rest of us?

That you might know

That's why John's words are so relevant to us today. He offers us certainty. Look again at verse 13: "I write these things to you who believe in the name of the Son of God, so that you may know that you have eternal life." That word "know" is very important to John. It appears more often in this chapter than in almost any other chapter in the New Testament. There are actually two words for "know" in the original language. In this verse, and most of the time in this chapter, he uses the word that describes the state of knowing rather than the process of knowing. When I say, "I know I'm an American," I'm declaring something I know to be true beyond a shadow of a doubt. When I say, "I know what it means to be an American," that's a knowledge I am still acquiring and growing into. One kind of knowing is complete and factual; the other is progressive and experiential. While both kinds of knowing are true of a Christian, it's the first kind of knowing, the certain kind of knowing, that John is emphasizing here.

And what it is John wants the church at Ephesus—and us—to know beyond a shadow of a doubt? Well, there are at least three things. The first thing he wants us to know is that eternal life is possible. That expression "eternal life" literally means "the life of the ages." In other words, a life for this age and the age to come. The word "eternal" speaks to both the quantity and quality of life. Eternal life is longer, in that it goes on forever. But it is also deeper, in that it encompasses the full range of human potential. Eternal life is real life—the life we were created to live and long to live. In fact, in the original language of verse 12, John doesn't just refer to it as "life," but as "the life"—"whoever has the Son has the life"—suggesting that any other kind of life falls short.

So the first thing John wants us to know is that eternal life is possible. The second thing he wants us to know is that this life is found in Jesus Christ. It's not something we find deep down inside ourselves, even though we were created with the capacity for it. It's not something we find out there in the world, even though this world was designed with that life in mind. Jesus Christ brought this life to us when he came to this earth and lived it for us. He showed us what it means to live life in full—in relationship with God and for the good of others. The world had never truly seen life as it was meant to be until Jesus came and lived it among us. So logically, the only place to find real life is in the One who actually lived it—Jesus Christ.

The third thing John wants us to know is that if you have the Son, you have the life. That's an interesting way to put it: having the Son and having the life. We know what it means to have an object, but how do you have a person? To have a person is to be in some kind of relationship with that person. When we say, "I have a spouse" or "I have a friend," we're declaring a certain kind of relationship. But it makes no sense to say "I have a stranger," because there is no relationship there; there's no definition. So to have Jesus Christ is to be in a relationship with him—a relationship defined by belief and trust and obedience.

And whoever "has the Son," John says, "has the life." Again, that's an interesting way to put it, especially in light of the words spoken by the Harvard president. "Truth is an aspiration," she said, "not a possession." Not according to John. When he says, "Whoever has the Son has the life," he uses a word that literally means "to possess, to own." There's a difference between aspiring to something and possessing something. For several months now we have been "aspiring to" own a piece of property in Wilmington for our new campus. We've been investigating it, pursuing it, and imagining what life and ministry will be like there someday. But we can't do anything with that land until we have it. John is telling us that eternal life—real life—isn't just something to aspire to, to long for, or to wonder about. Eternal life is something you can have now.

Last weekend I talked Karen into seeing the movie Hereafter. I hadn't heard much about it, but Matt Damon was in it, so it couldn't be that bad. At the very least, it was sure to provide some sermon material. As it turned out, it was pretty bad, but it did provide some sermon material. The movie attempts to explore life beyond this life by following three characters who have close brushes with death and/or the afterlife. It doesn't offer much in the way of answers, other than to suggest that there is something more beyond this life, and that it's probably going to work out okay for most people.

The character played by Matt Damon has psychic abilities; he's able to communicate with the dead. So one of the characters comes to see him and asks him to contact a loved one who's died. As Damon makes a connection, he begins asking the spirit questions on behalf of the one who's been left behind: What's it like there on the other side? Can he come join him there? What should he be doing, now, on this side? As the scene was unfolding on screen, I turned and looked around the theater, which was full, and realized you could hear a pin drop. No one was moving. No one was munching popcorn or sipping soda. Everybody's eyes were fixed on the screen. They were hanging on every word. And it hit me: they wanted to know, too. They wanted to know for themselves, What's it like on the other side? Will we all get there someday? What should we be doing in the meantime? They wanted to know so badly that they were willing to believe Matt Damon might be able to tell them.

You see, people want to know. In a frightening and fast-changing world with foundations crumbling around us, what can we count on? What can we know, for certain?

Well, this much we can know, according to John: Eternal life is possible. It's found in Jesus Christ. And if you have a relationship with Christ, you have eternal life. You don't have to wonder or wish or hope. You can know, for certain. In fact, John wrote this letter for that very purpose. Look again at verse 13: "I write these things to you who believe … so that you may know that you have eternal life."

The believer's journey

This is very interesting! John wrote this letter for a very different purpose and audience than he had in mind when he wrote his gospel. If you go back to John's gospel, as he comes to the end in chapter 20, he tells us why and for whom he wrote: "But these are written that you may believe that Jesus is the Christ, the Son of God, and that by believing you may have life in his name" (John 20:31).

You see the difference? John wrote his gospel for seekers, so that they would come to believe. He wrote his letter for believers, so they would come to know. The letter picks up where the gospel leaves off. In fact, when you put John's gospel and his letter back to back, you discover that John has mapped out the journey of faith.

According to John, the spiritual journey begins with hearing—understanding the life and message of Jesus. The next step is believing—putting your trust in the life and message of Jesus. These first two steps, or phases, are the purpose of his gospel. The next step in the journey, according to John, is living—not just trusting Christ, but actually following Christ in everyday life. That's what he's been writing about in this letter—walking in the truth, doing what's right, loving one another. Doctrinal, ethical, relational expressions of faith. And when you're actually living your faith day by day, it leads you into the final phase of the journey: knowing—having complete confidence that you are God's child, now and forever.

Recently I was with a group of pastors at conference. We were introducing ourselves to one another, and one of them said, "My name is Jim. I'm a writer." At that moment our ears perked up, because, truth be told, every pastor wants to be a writer. "What do you mean, 'you're a writer?'" someone asked.

Turns out the writer's name was Jim Belcher, and he's the author of Deep Church, the book I mentioned a few weeks ago that our elders are reading. Not only that, he's currently working on another book, for which he's already received an advance! And he recently moved his family to Oxford, England, so he could write better!

Here's my point in telling this: all of us in that little circle want to be writers. We dream about writing. Most of us have done a little bit of writing, but none of us would dare to call ourselves "writers." But Jim Belcher can legitimately call himself a writer. Why? Because every day he wakes up and he writes! Because there's a book out there with his name on it! Because he's taking steps every day to becoming an even better writer.

In a similar way, you know you're a child of God when you live like a child of God. If you're growing in your knowledge of Christ, if you're becoming more like Christ day by day, if you're learning to love others, you're already living eternal life! And if you're already living it, then you know, for certain, that you have it.

Hearing, believing, living, knowing. Do you see what direction we're moving in? Up and to the right! This is the spiritual journey! This is the road map! And our destination is here: knowing. Because when you get to the knowing stage you're no longer bogged down by fear and doubt and worry. You can enjoy the journey, you can live the life, because you know where you're going.

Let's say you're on a road trip. You're taking the family on vacation to a beautiful little lake tucked away in the hills of Maine—Tucker Lake, we'll call it. So you all pile into the car and head north. Everyone's excited, enjoying the scenery, and looking forward to a week in the cabin by the lake. After a couple hours you get off at exit So-and-So and follow the main road, just like they told you.

But it turns out the main road isn't so easy to follow. There are twists and turns and forks and rotaries, and before long you don't know where you are or where the main road is. And suddenly no one is having a good time anymore. You and your spouse are arguing with each other. The kids are fighting in the back seat. The dog is carsick. And the thought of spending a week in a cabin by the lake doesn't sound nearly as wonderful as it did a few hours ago!

Just then, you come to another fork in the road, only this time there's a sign: "Tucker Lake: 21 miles." You breathe a sigh of relief. You and your spouse smile at each other. The kids start looking out the window, and everybody's looking forward to a week at the cabin by the lake. Why? Because you know you're on the right road. You know where you are and where you're going. You can relax and enjoy the journey. That's the kind of assurance, the kind of certainty, John offers to his readers and to us. So many people are making their way through life without really knowing where they are, where they're going, and whether they're on the right road or not. It makes for an unhappy and unsatisfying journey. When you know where you're going, it changes everything.

In the grip of the evil one

It turns out there's one more thing John wants us to know. He doesn't want us to be under any delusions about the kind of world we live in. Look down at 20:19: "We know that we are children of God and that the whole world is under the control of the evil one."

We live in a fallen world. Satan is on the loose. People do foolish and terrible things. The forces of nature run amuck sometimes. As Nina acknowledged in her letter, God never promises freedom from pain, hardship, or disappointment in this life, even for his children. We live in a fallen world. It's important to know that, because then you no longer expect this world to deliver ultimate peace and joy and love.

"We also know," says John, "that the Son of God has come and has given us understanding so that we may know him who is true. And we are in him who is true, even in his Son, Jesus Christ. He is the true God and eternal life" (1 John 20:20). This world may be fallen, but God has come into this world and brought life with him. We don't have to worry about the future. We don't have to wonder what's going to happen to us in the life to come. The life to come has already come! Jesus brought it with him when he came! We're already living it! And if we're already living it, then we know, for certain, that we have it! Eternal life isn't waiting for us in the hereafter; it's here now, in Jesus Christ. And when we know, for certain, that we have eternal life, we can deal with whatever this life throws in our path.

At the World Congress in Cape Town, we heard a remarkable testimony from a young Korean girl. Sung Kyun was born in North Korea, but at age six, she and her family fled to mainland China. Some relatives led them to a church, and Sung Kyun's parents became Christians. At one point, her father had to return to North Korea, where he was a government official. He tried to share the gospel there and was imprisoned as a result. Meanwhile, back in China, Sung Kyun's mother died in childbirth, and Sung Kyun had to live with relatives. Eventually, her father was released and returned to China, but he was so burdened for his people back in North Korea that he went back, of his own free will, to share the gospel. Again he was arrested, only this time he was never heard from again. Back in China, Sung Kyun saw Jesus in a dream. She began reading the Bible for herself and became a Christian. She's now attending university in China, studying to be a diplomat, so that she can go return to North Korea in an official capacity. "I want to bring the love of God to North Korea," she said, with tears in her eyes and resolve in her voice.

Sung Kyun knows who she is. She knows why she's here. She knows what this world is like. And she knows where she's going. When you have that kind of knowledge, that kind of certainty, you can deal with anything the world throws in your path—you can take risks the world would never take.

None of us knows what the future holds for us, for our children, and certainly not for our grandchildren. What we do know, for certain, is that God has given us eternal life and that this life is in his Son. Whoever has the Son has the life. When you know that, you can face anything.

And that leads us to John's final message for us in this series: You know you're living deep when you can face the future with confidence, knowing your life is in God's hands, now and forever.

Your road map

So let me bring us back to the spiritual journey John mapped out for us: hearing, believing, living, knowing. Where would you put yourself on that road map? Maybe you're still in the hearing stage, still investigating the life and teachings of Jesus. That's okay; you're on your way. Maybe you have come to believe the message of Jesus sometime recently or in the past. That's good; that's an important step. That's when you're born again and become a child of God. But you don't want to get stuck there, merely believing. That's no fun at all. You want to start living your faith, growing in your knowledge, becoming like Christ, giving of yourself to others in love. Because once you start living your faith, you suddenly find yourself in the knowing stage, where you no longer worry and wonder, but instead step out in confidence every day, knowing who you are, why you're here, and where you're going.

For Your Reflection

Personal growth: How has this sermon fed your own soul? ___________________________________________

Skill growth: What did this sermon teach you about how to preach? ____________________________________________________________________________

Exegesis and exposition: Highlight the paragraphs in this sermon that helped you better understand Scripture. How does the sermon model ways you could provide helpful biblical exposition for your hearers? ____________________________________________________________________________

Theological Ideas: What biblical principles in this sermon would you like to develop in a sermon? How would you adapt these ideas to reflect your own understanding of Scripture, the Christian life, and the unique message that God is putting on your heart? ____________________________________________________________________________

Outline: How would you improve on this outline by changing the wording, or by adding or subtracting points? _____________________________________________________________________

Application: What is the main application of this sermon? What is the main application of the message you sense God wants you to bring to your hearers? ____________________________________________________________________________

Illustrations: Which illustrations in this sermon would relate well with your hearers? Which cannot be used with your hearers, but they suggest illustrations that could work with your hearers? ____________________________________________________________________________

Credit: Do you plan to use the content of this sermon to a degree that obligates you to give credit? If so, when and how will you do it? ____________________________________________________

Bryan Wilkerson is pastor of Grace Chapel in Lexington, Massachusetts.

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Sermon Outline:


I. A culture of doubt

II. That you might know

III. The believer's journey

IV. In the grip of the evil one

V. Your road map