← Back to sermons

Purity to Make a Difference

Different to Make a Difference

Watch on YouTube →
Preacher
Mark Pettus
Church
Church of the HighlandsNon-DenominationalIrondale, United States
Date
Sunday 12th July 2026
Read time
17 min
Language
English

Scriptures

1 Peter 2:91 Corinthians 6:12Ephesians 5Romans 14:23Psalms 24:8-9Revelation 3Romans 10:13Psalms 51Matthew 52 Corinthians 7:11 Peter 2Romans 14Psalms 24

Tags

Categories

Christian LivingDiscipleship

Bible Characters

DavidPaulJesus

Key Takeaways

  • Christianity has always been different, and we are called to live differently in order to make a difference and point people to Jesus.
  • For Christians, sex is not merely an appetite but a covenant gift to be enjoyed within marriage, and the body is a temple to honor.
  • Paul's P.U.R. filter helps us live pure lives: Is it Pleasing to God? Does it Uphold my convictions? (based on Scripture and the leading of the Holy Spirit).
  • No one can ascend the mountain of the Lord on their own merit; God came down to us, and the best part of God's day is forgiving us.
  • Whether you need to be saved or cleansed, God stands at the door and knocks, ready to come in and create a clean heart.

Need another language?

Checking translation support for this browser...
In this sermon

Christianity Has Always Been Different

All of these numbers are not normal. It's different to see 20,000 people serve. It's different to fill up an arena with young people. But here's the key idea for this whole series: Christianity has always been different.

We're not going to shy away from that. We are going to boldly celebrate the fact that God has called us to be different, and God has called us to live differently in the world we're living in right now. Not different just to be different — I want to be clear upfront. We're not looking for any attention to be drawn toward us.

Here's the theme of the whole series: we are different to make a difference. We live differently so that we can point people to Jesus. That's what our key scripture says:

"You are a chosen people. You are a royal priesthood, a holy nation, God's special possession, that you may declare the praises of him who called you out of darkness into his wonderful light." — 1 Peter 2:9

Somebody just needs to receive this today. If it would have just been you, he'd have gone to that cross just for you. He has saved us and rescued us — let that never become old news. That is good news! But it comes with a job description: because of what he's done in our lives, we can declare his praises.

I was 17 when God called me out of darkness into his wonderful light. Now we get the beautiful opportunity to share that story with others. That's what it really means to be a follower of Jesus: to know him and to make him known.

How the Church Actually Grew

Think about the history of Christianity. Jesus is born, lives a perfect sinless life, does public ministry for three years, and goes to the cross. On Good Friday he dies, and he is placed in the tomb — but Easter was coming. Three days later he comes out of that grave. For 40 days he equips his disciples, then he ascends to heaven, and 10 days later the Holy Spirit descends into that upper room. That is the day the church of Jesus Christ was born.

On that day, Peter preaches a sermon and at least 3,000 people give their hearts to Jesus. At that moment, the entire church was just three to five thousand people. Now fast forward 300 years, and despite crazy opposition, plagues, and Roman persecution, there are now millions of Christians. How did we go from twelve disciples to millions, to what we see now — billions across the planet?

I'll tell you how it didn't happen. It did not happen because we blended into culture. And it didn't happen because we were put in charge.

A sociologist named Rodney Stark studied this question in the 1990s. In those early decades the church was growing 40% per decade. When he started his research, he was an agnostic with no faith at all — but the more he studied, the more he ended up giving his heart to Jesus. That'll preach in itself.

Here's what he found:

Christianity's growth wasn't primarily driven by miracles or preaching. It was the kind of life that Christians lived.

We were different, and that made a difference. Here's an excerpt from his book:

"To cities filled with the homeless and impoverished, Christianity offered charity as well as hope. To cities filled with newcomers and strangers, Christianity offered an immediate basis for attachments. To cities filled with orphans and widows, Christianity provided a new and expanded sense of family. To cities torn by violent ethnic strife, Christianity offered a new basis for social solidarity. And to cities faced with epidemics, fires, and earthquakes, Christianity offered effective nursing services."

You know what that tells you? Serve Day was never our idea. Serve Day has been happening since the beginning. This is the history of our faith.

Salt and Light — Attractive and Offensive

This series is an equipping series. I feel deep in my spirit that we are heading into a fall where revival is happening in America right now. This series is about equipping us to get ready for what God wants to do through all of us — that we would live differently, and that it makes a difference.

There are four areas we're leaning into: generosity, purity, forgiveness, and community. These aren't just our ideas. This is what Jesus commanded:

"You are the salt of the earth... You are the light of the world." — Matthew 5

God has called us to be attractive, but also — because of the way we live — a little offensive. People are going to look at us and say, "I love a lot of what they're doing, but I'm not sure I like all of it. It's so different. It's attractive and offensive."

Can you think of anything in your life you love and hate at the same time? My gym people know what I mean. Lately I've started cold plunging — I'm never excited to get in, but when I get out I feel better. It's like broccoli, hot sauce, or Taco Bell: you may love it when you eat it, but a day later you hate it. And I love that Chick-fil-A is closed on Sunday — but I kind of hate it, because I never want it more than on a Sunday.

So God has called us to be attractive, but we've got to understand it's also going to be offensive at times — and maybe on no topic more than purity.

The World's View of Purity

When we talk about purity, a lot of us immediately think of sexual purity, and I do want to lean in there for a moment, because we are called to be different in that area. That was true in Rome, and it's definitely true in our culture. Let me capture the spirit of the age:

  1. Sex is an appetite to satisfy. The world sees it as no different than hunger or thirst. That was true in Rome, and it's true today — except now through instant access: the internet, apps, pornography, 24/7 on demand. "What happens in Vegas stays in Vegas" — an entire city built around that kind of pleasure.

  2. The body is a commodity to use. Some statistics have grabbed my heart. Pornography is a hundred-billion-dollar business every year. Sex trafficking is a $173 billion-a-year criminal enterprise. I feel that we as a church are called to do everything we can to rescue those precious children and women, to come alongside ministries, and to pray for that wicked spirit to be broken. Bodies are treated as something to sell.

  3. "If it feels good, do it" is a doctrine to obey. And that always leads to misery. It was said of Rome — and could be said of America — that the soul of the society was rotten.

When Christianity came along, it was like, "Oh, there's a better way." We're living in that same kind of moment. When we live differently, it makes an immediate impact.

The Christian Difference

Sex Is a Covenant Gift to Enjoy

Christianity offered what historians call the first sexual revolution. For us, sex is not an appetite — it is a covenant gift to enjoy. Sex is designed for marriage, one woman and one man. Not because God is old-fashioned, but because he made us and knows the best way for us to live. He invites us into abundant life.

A non-Christian philosopher observing early Christians in Rome wrote:

"They marry like other men and they beget children, but they do not cast away their offspring. They have their meals in common, but not their wives."

They lived in covenant, and it made a difference. In our day, when we simply live the way God has called us to live, people are going to notice, and it's going to make a difference.

The Body Is a Temple to Honor

This is probably the most important thing I can say today:

"Do you not know that your bodies are temples of the Holy Spirit... You are not your own; you were bought at a price. Therefore honor God with your bodies." — 1 Corinthians 6

This building is not the temple — our bodies are the temple of the Holy Spirit. We've been bought with a price. Jesus went to that cross and died for us so that we could live. In response, we honor God with our bodies.

The world says, "If it feels good, do it." But our truth is: if it is good, do it. Instead of a rotten soul, that leads to abundant life.

Biblical Purity Defined

I want to expand this teaching beyond just sexual purity to the concept of purity from Genesis to Revelation. There are two words I want to teach you.

  • In the Greek: Catharos — clean, clear, like clear water.
  • In the Hebrew: Tahor — pure, unmixed, like pure gold not mixed with other metals.

Biblical purity holds both of those ideas at once. Here's my definition:

Biblical purity is a life that is clean and whole — not polluted by sin and not divided by competing loves.

Sometimes we imagine only the "not polluted by sin" part, but it also connects to not having a divided heart, not being divided between competing loves — no idolatry in our hearts. If you call yourself a Christian, this is how God calls us to live. This is his standard.

"Since we have these promises, dear friends, let us purify ourselves from everything that contaminates body and spirit, perfecting holiness out of reverence for God." — 2 Corinthians 7:1

Does that say 50%? 70%? 99.9%? No — everything.

"Live such good lives among the pagans that, though they accuse you of doing wrong, they may see your good deeds and glorify God." — 1 Peter 2

They're not going to glorify us. It's about them seeing Jesus.

My Story: The Witness of the Different

I wouldn't be on this stage without a group of people who lived this way.

I grew up in a small town — Lineville, Alabama. Don't blink, you'll miss it. We're proud of our Piggly Wiggly and our four dollar stores. We were part of First United Methodist Church downtown. I grew up in church with amazing parents, but honestly God wasn't a big focus of our family. It was part of our tradition.

I was sprinkled as an infant. In Sunday school I learned quickly that no matter what the question was, the answer was almost always "Jesus" — and I'd get caught not paying attention, so I'd just say "Jesus" and I was right 99% of the time. I loved Vacation Bible School — the crafts, the hot glue gun, the Kool-Aid (which is always better at church, by the way). But I never really connected with God.

When I was 13 or 14, I drifted away. I'd never had a real relationship with God, and I was just trying to find my own identity — trying on hats. If there was a party on the weekend, if they were drinking, I'd be part of it. My parents knew none of it. It was all in secret. I felt horrible on the inside, but I was really just searching.

One night I went to a friend's house where his single mom had a big liquor closet. We broke into it, and of course we got caught. The next morning she called my parents. They came down to my room and told me they'd received the phone call. My whole secret life came out in that moment. What hit me hardest was when they said, "We love you, Mark, but we're so disappointed in how you're living." That broke my heart.

My parents were old school. They grounded me — three months, full on — from everything except church. Don't ever ground your kids from church. That's what got me back.

I walked into that little youth group, and for two or three months it wasn't a sermon or any formal program. I just watched these teenagers. They were not perfect, but they were living for God, saying yes to him and no to sin. It was their testimony, their life. I said yes to Jesus at 17 because of the witness of those who were different and made a difference.

The PUR Filter: How to Live a Pure Life

So how can we live pure lives in this crazy world? Through the Apostle Paul, God gives us a filter.

"I have the right to do anything, you say — but not everything is beneficial. I have the right to do anything — but I will not be mastered by anything." — 1 Corinthians 6:12

Without God, I can do anything. So how do I go from all the things I can do to the things I should do? Here's the filter — P.U.R.

P — Is it Pleasing to God?

This is my first question when facing any lifestyle decision.

"For you were once darkness, but now you are light in the Lord. Live as children of light... and find out what pleases the Lord." — Ephesians 5

I love that it puts this as a personal responsibility: go find out. And the good news is we have a manual — the B-I-B-L-E. Before I say yes or no to anything, I get into the Word of God. What does God's Word say about money? About relationships? About forgiveness?

  • If his Word says do it, we're going to do it.
  • If his Word says don't do it, we're not going to do it.

When he marks something as sin, or as part of our mandate, case closed — we're Bible people.

But there are other things that live in a grayer place, where God doesn't specifically speak. In those moments, he calls us to the second part of the filter.

U — Does it Uphold my Convictions?

"But whoever has doubts is condemned if they eat, because their eating is not from faith; and everything that does not come from faith is sin." — Romans 14:23

The example is eating, but you can expand it to any area. If you do anything you believe is not right, then for you it is sin.

The Bible is the standard for us all, but convictions are things God speaks to us uniquely — never in contradiction to his Word. That means how we follow God will look different for each of us. There are things I feel free to do that you may feel conviction not to do, and vice versa. How do we discover them? Through relationship with the Holy Spirit.

Anywhere the Bible is clear, you'll never see me back away one inch — I'll die for this Word. But I get asked all the time to take a bold public stance on things like music, movies, drinking, voting, school choice, Harry Potter, Halloween, or tattoos. Those are convictions best worked out one-on-one or in a small group.

Here's my one confession on tattoos: I don't have any, but my best friend Blake has lots of them. Figure it out.

Develop personal convictions fueled by the Holy Spirit — and then live by them, because if you don't, you're sinning.

R — Does it Represent God's Kingdom?

This is all about the love of God. No other faith has even imagined a standard like this. God calls us at times to lay down things we would normally do — to lay down our rights for the sake of others — never violating his Word or our convictions.

"Let us stop passing judgment on one another. Instead, make up your mind not to put any stumbling block or obstacle in the way of a brother or sister. I am convinced, being fully persuaded in the Lord Jesus, that nothing is unclean in itself. But if anyone regards something as unclean, then for that person it is unclean. If your brother or sister is distressed because of what you eat, you are no longer acting in love. Do not by your eating destroy someone for whom Christ died." — Romans 14

Look how Paul gives all three filters in one passage: the Word ("nothing is unclean in itself"), conviction ("for that person it is unclean"), and love ("you are no longer acting in love").

The third question is: What does God's love require of me? This matters for our witness and our unity. It's so easy to get judgy in the house of God — never on the big things we all agree on, but on the small things around personal convictions. We're not going to do that. We're going to be a people of unity, focus on the majors, and push people to Jesus.

If something gets in the way of us, I'll lay it down, because I love you and want to do life with you. And if it gets in the way of us sharing Jesus with the world, it's not worth it. How can we put a stumbling block in anyone's way?

Putting It Together

What is confusing, chaotic, and crazy 24/7 gets clarified when we run it through the filter. P.U.R.:

  • Pleasing to God?
  • Upholding my convictions?
  • Representing God's kingdom?

Now we know how to live the way God has called us — unmixed with the world around us.

The King of Glory Came Down

I've left a tension hanging on purpose. Every time I preach on purity, I feel the pressure in the room increase, because the enemy has a way of bringing condemnation — stirring up guilt, making us think of all the ways we've messed this up. Myself included. At the same time, we cannot deny that purity is a big deal to God.

"Who may ascend the mountain of the Lord? Who may stand in his holy place? The one who has clean hands and a pure heart, who does not trust in an idol or swear by a false god." — Psalm 24

That's the clearest reminder that purity matters to God — but it may be one of the heaviest verses in my own life. Because if I know my past, I don't have clean hands and a pure heart. So how will I ever see him?

Maybe you walked in carrying guilt and condemnation from a decade ago, or from last night, or even this morning. And the honest answer to "Who may ascend the mountain of the Lord?" is: no one. All have sinned and fallen short of his glory.

But David doesn't stop there:

"Who is this King of glory? The Lord strong and mighty... Lift up your heads, you gates; lift them up, you ancient doors, that the King of glory may come in." — Psalm 24:8–9

We could never ascend that mountain — so God didn't call us up the mountain. He came down to us. The King of glory came in when we couldn't go up.

What is God doing right now?

"Here I am! I stand at the door and knock." — Revelation 3

No one can ascend that mountain, so he says, "I'm ready to come in." God wants to come into your heart today and purify you.

Let Him Save You

For some of you, that means today, let him save you.

"Everyone who calls on the name of the Lord will be saved." — Romans 10:13

I don't care what your résumé is. I met a man yesterday — John — 25 years in prison, who said yes to Jesus and now lives for him. He got saved because of a hygiene kit, and yesterday he was making hygiene kits to send back into the correctional facilities. If God can save me, if God can save him, he can save you. You don't have to clean up first. He wants in, and all the mess. Just let him in.

Let Him Cleanse You

For those who are already saved but still wrestling — you can receive today the fresh grace and mercy of Jesus. In the Bible Belt, we often see God incorrectly, out of a religious mindset, like a bank account you can't withdraw from. We imagine the worst part of God's day is forgiving us. Nothing could be further from the truth. The best part of God's day is forgiving you. It was for the joy set before him. Don't steal God's joy today. Let him create in you a clean heart.

Closing Prayer

Let's pray together.

God, I thank you for your presence right now. I thank you for the higher standard you've called us to — and the fact that you called us there through your strength, not our own; through your grace, not our own.

If God is speaking to you and you need to get saved today — or maybe it's a rededication — pray with me:

Jesus, today I give you my life and I open the door to my heart. King of glory, come in. Do what I can't do. I turn away from my own strength. I declare you my Lord and Savior. Fill me with your Holy Spirit so I can live for you.

And for anyone who is a follower of Jesus ready to let go of some things and be washed white as snow, pray the words of Psalm 51:

God, create in me a clean heart. Forgive me. I was wrong when I did this — it was not your will. I repent right now. Renew in me a steadfast spirit. Restore to me the joy of my salvation.

God, we're praying for your strength to walk away from those things and live differently today. Let guilt and condemnation be broken, and let there be a new joy. Overwhelm us with your love, in Jesus' name. Amen.