This Is Serious
Sermon preached at Hickory Presbyterian Church on August 26, 2026

A few weeks ago I had a routine colonoscopy. Nothing dramatic, just one of those things you do at a certain age and then thank the Lord when it’s over. I was in one of those outpatient surgery centers, lying behind a curtain, waiting for my turn to come. And while I waited, I could hear the conversation happening in the next bay over. I never saw the man’s face. I don’t even remember most of what the doctor said. But I remember one sentence, spoken quietly and without any drama at all.

“Sir, this is serious.”

The doctor had found cancer spreading through this man’s colon. It had to be dealt with immediately. And can I tell you what struck me, lying there behind that curtain? That doctor didn’t soften it. He didn’t say “it’s probably nothing” or “let’s just keep an eye on it.” A good doctor tells you the truth, even when the truth is hard to hear. Because ignoring a disease doesn’t make it go away. It just gives it time to spread.

That’s exactly what’s happening in Mark 9:42-50. Jesus pulls up a chair beside every one of us. He looks us in the eye. And He gives us a diagnosis. Not cancer. Sin. And He says the same thing that doctor said. This is serious.

Honestly, left to ourselves, we would never believe how serious sin really is. We’re experts at making it sound respectable. “It’s not that bad.” “Everybody struggles with something.” “I’ll deal with it later.” We compare ourselves to people who look worse than us and call that righteousness. Jesus doesn’t let us get away with that. Not because He’s harsh. Because He loves us too much to let us die of something we’ve convinced ourselves isn’t serious.

Somebody Is Watching You

Before Jesus ever talks about your sin, He talks about how your life affects other people. That surprised me as I sat with this text. He says whoever causes one of these little ones who believe in Him to stumble, it would be better for that person to have a millstone hung around his neck and be thrown into the sea. Not a small stone you could tuck away. The kind a donkey pulled. Once it was around your neck, there was no swimming out of that.

And Jesus says that would be better. Not good. Better. Because there’s something worse than drowning.

Here’s what got me this week. Nobody follows Jesus alone. Somebody is watching you, whether you feel the weight of it or not. Your kids are watching what following Jesus actually looks like at your kitchen table, not just what you say on Sunday. Young adults, your friends are watching what you post, what you laugh at, what you chase after. Older saints, don’t you dare believe the lie that your usefulness is behind you. Somebody is watching how you suffer, how you finish. Your life is preaching a sermon every single day whether you meant to write one or not.

Did a name come to mind while you read that? Maybe there are words you wish you could take back. I know I have some. We’ve all failed somebody. If that’s where your heart is right now, don’t stay there. That’s not what this warning is for. It’s not meant to drive you away from Jesus. It’s meant to drive you to Him.

Kill It Before It Kills You

Then Jesus turns from how we affect others to something more personal. If your hand causes you to sin, cut it off. If your eye causes you to sin, tear it out. Hard words. They’re meant to be. Jesus is not handing out a surgery manual here. Your hand isn’t the problem. Your heart is. Your hand just does what your heart already wants. Jesus is describing your whole life, everything you do, everywhere you go, everything you desire, and He’s saying, whatever it is, deal with it. Today.

What is it for you? Maybe it’s a grudge you’ve been nursing so long it feels like part of your personality now. Maybe it’s a habit nobody else knows about. You know. Jesus knows. And He’s not looking for a reason to condemn you. He’s looking to free you, because sin never stays where you leave it. It always asks for more. As John Owen put it, be killing sin, or it will be killing you.

Jesus talks about hell three times in this passage, more than anyone else in all of Scripture. That should tell us something. The one who speaks most about God’s love also speaks most about God’s judgment, because both are real, and because He loves sinners enough to warn them before it’s too late.

He Doesn’t End With Hell

But here’s what I don’t want you to miss. Jesus doesn’t stop at the diagnosis. He ends with hope. Every sacrifice offered to God was seasoned with salt, set apart, belonging to Him. If you belong to Christ, you belong to Him completely, and He isn’t finished with you. Some of you are in the fire right now and you didn’t ask for it. Sickness. Grief. A child who’s wandered. A burden nobody else knows you’re carrying. Hear me. God hasn’t forgotten you. He isn’t punishing you. He’s refining you, and one day you’ll see that not one tear was wasted.

The doctor who told that man the truth could diagnose him. He could recommend treatment. But there was one thing he could never do. He could never take his patient’s place.

Jesus did. His hands never sinned, yet they were pierced. His feet never wandered, yet they were nailed to a cross. And on that cross the judgment our sin deserved fell on Him instead of us, so that everyone who repents and believes would never have to face it. That’s the gospel. That’s why this warning isn’t meant to crush you. It’s meant to send you running to the only One who can save you.

So whatever the Lord has shown you today, don’t carry it out of here. Bring it to Christ. He welcomes repentant sinners. He forgives them. He restores them. And because the Good Shepherd laid down His life for His sheep, His sheep will live forever.

Listen to the full sermon here: This Is Serious (Mark 9:42-50)

And worship with us Sundays at 10:30 AM at Northview Middle School Auditorium, 302 28th Ave NE, Hickory, NC (behind Publix on Hwy 127). We’d love to see you.

Tripp Castell
Pastor, Hickory Presbyterian Church