Note: Read Part 1 or Part 2 here.

The new year is upon us. And with new years come new resolutions. Of course, these resolutions are largely new commitments to better behavior. How long will they last this year?

Here’s the great news of Christianity; regardless of resolutions made or kept, believers are new people. And with our new birth comes new behavior. Did you catch that? You can have a new teenager in your home this next year! Her behavior can be Christlike. His conduct can be more godly.

But how does this new behavior happen? What are the steps? The Apostle Paul details the pattern of new living in the closing verses of Ephesians 4, but before he tells us what to do, he first reveals how to think. My former professor, Michael Barrett, writes, “Right thinking about the gospel produces right living in the gospel.”1 In other words, your teenager’s thinking will determine his or her behavior.

Far too often in discussing Christian teenage sanctification, we rush to conduct without first understanding our doctrine. In other words, we are quick to talk about how to act as a Christian and spend precious little time on how to think as a Christian. And this routinely leads to failure in living for Christ.

Have you ever wondered why it seems so many of our young people drop out of church once they graduate high school? Certainly there are multitudes of reasons, but I believe a big factor in our losing the next generation is that we have perhaps unwittingly exhorted our teenagers to do Christian conduct divorced from Christian doctrine. They have the impression Christianity is nothing more than a life of morality with a little bit of Jesus thrown in.

We admonish them to be kind, to be loving, to tell the truth, and to be full of integrity. We also exhort them to avoid anger, to stop lying, to run from immorality, and to never cheat or steal. We provide our teens with the ever growing list of moral do’s and don’t’s, and as long as they are checking off the boxes, they’re good Christians.

Here’s the problem with that thinking: that’s not Christianity. Now all those behaviors are commendable, and I would argue a Christian will be conducting himself that way, but you don’t have to be a Christian to check any of those boxes.

How many non-Christians do you know who are good, moral citizens? Far be it from me to say any of this conduct is bad, but many consider themselves “Christian” because of what they do or don’t do. The Bible is clear, however, that becoming a Christian is not something you do; it is something that is done to you by the Holy Spirit of God (Titus 3:5).

Then, once you become a Christian, the Lord requires you to behave like Christ. And He has given you the power to do so. We do not diminish Christian conduct in the home, but your teenage daughter and son must understand that their Christian conduct always follows Christian doctrine. If we do not take the time as dads to first teach our children what happened to them at salvation, we will end up only teaching moralism, and we will be no different than the good, decent, moral atheist.

Question for you: can a person be moral without having faith in God? Absolutely! Pagan morality aims to be good without God. In fact, a person who rejects God while still holding to morality jumps straight to his conduct as proof of his goodness. He says, “Of course I’m a good person; look at my good deeds.” But Christianity first jumps to Christ. We say, “We are good only because of what Jesus has done for us.”

I like to work this out in a familiar scenario. The preacher speaks directly to the teens, “Young people, don’t you be sleeping around!” And then follows the reasons why—the thinking behind the conduct. “After all, you could get pregnant and endure the shame and difficulty of a teenage pregnancy. On top of that, be sure your sins will find you out! Your dad will kill the both of you once he discovers you’ve been immoral. And then, don’t forget about the consequences of STD’s! Teens, be morally pure.”

Now I suppose those reasons to avoid immorality can be powerful deterrents to bad behavior, and a case could be made to use such arguments. But again, an atheist guidance counselor who cares about teens could give them the same warnings. There is no Christ in that counsel. Therefore, moralism is not Christianity!

The gospel says your teenage daughter has been saved by Someone greater than her. The Holy Spirit has created your teenage son as an entirely new person who now lives an entirely different life. There are sinful behaviors and wicked decisions unthinkable to them now because of what has happened to them! From one father to another, let us not preach moralism to our teenagers; let us preach Christ!

This is exactly what the apostle is doing in Ephesians 4:25. He begins with the word therefore. This word is a big, beautiful bridge connecting Christian doctrine with Christian duty. Perhaps a simple chart of Ephesians 4:22–32 will help.

4:22–244:25–32
Christian doctrinethereforeChristian duty
What is truethereforeWhat you must do
Identity in ChristthereforeActivity for Christ

Now let’s spell it out in long form. In Ephesians 4:22–24, the apostle tells us the truth as it is in Jesus. As dads, we must remind our teenagers of these truths. When they came to faith in Christ, the old self was put away. Simultaneously, the new self was put on once and for all. And now every day, the Holy Spirit renews their minds and recalibrates their thinking in Christ. This is supernatural! This is irrevocable! Something vital has happened to them entirely by God!

And then we walk over the therefore bridge into Ephesians 4:25–32. Your teenager has put off the old self, so therefore they should daily put off the corruption the old man left behind. They have put on the new self, so therefore they should daily put on the righteous conduct of the new man. This is Christianity! We do not preach morality; we preach Christ.

So yes, a new year is coming. By God’s grace, as we marry Christian doctrine with Christian conduct, we will see our new teenagers producing new behavior in this new year.


  1. Barrett, Michael P. V., Complete In Him: A Guide to Understanding and Enjoying the Gospel, (Greenville: Ambassador-Emerald International, 2000), 3. ↩︎

Andy Gleiser

Growing Fathers Team

Andy is a husband to beautiful Bryn, dad to 3 great kids, pastor, hymn writer, and church planter who enjoys preaching, baseball, and westerns. He lives with his family in Reno, NV.

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