There are a few things I've learned since I became a Christian. As Paul says in Romans 7 "When I want to do good, evil is right there with me" (Romans 7:21). I hope, as you grow up, you'll learn these things as well. Here are some "truths" I have come to believe since becoming a Christian:
Every person has two natures inside us—a sinful nature and a godly nature.
The sinful nature’s sole purpose is to live for the “now” and will do whatever it can to protect itself. Things like lying, cheating, hurting others, watching inappropriate videos (either pornographic or videos that are "close" to pornographic), disrespect, and similar things are part of that nature.
The godly nature’s purpose is to live for others and to please God. It is not focused on the “now”—it’s focused on the “best”. What is best for us doesn’t always feel good now.
4.We all have free will. We can choose whether to follow the sinful nature, or to follow the godly nature. However, we will all follow the sinful nature instead of our godly nature at some point every day.
Why fight it then? If we are destined to fail, why not just give in?
It hurts us in the long-term. A good example is what happens when we eat too much greasy food or sweets. They taste very good in the “now” (the sinful nature), but later, we feel sick. So we choose to eat the sweets or greasy food in moderation because we don’t want to be sick later.
When we give in, the sinful nature is a spiral that leads us into worse and worse situations. And we don’t realize how much we’ve been damaged until it is too late. A good example is when we’re caught doing something we shouldn’t. Our first reaction (sinful nature) is to lie to get out of it. But it just leads to more trouble and more damage.
Doing what’s “best” will always lead to good things in the end. A good example is studying. It doesn’t feel good now to study or do homework. But when we do, we get good grades. And when we get good grades, we feel good about ourselves, we will be rewarded by our parents, and we learn.
Physical (sexual) desires are neither part of our sinful nature nor our godly nature. They’re just feelings and desires. But our sinful and godly natures want very different things with those feelings.
The sinful nature wants to please it now. Look at pictures, masturbate, see how far you can get with someone. But this destroys relationships and it destroys your mind. Eventually, you become enslaved. You can’t get away. You’re like a dog that humps legs.
The godly nature wants those feelings to be channeled toward later—that special person you’ll eventually marry. Now that may be a long time and seems impossible to control the desires. And we will fail. But as long as we’re trying, God will give us strength to repent and start going again.
How do we channel our sexual desires so they don’t enslave us?
Talk to a godly person about your struggles. Bring it into the light.
Recognize the places you’re tempted most and either avoid the place, or make it hard for yourself to fall. If you watch inappropriate videos on your iPhone in the bathroom, don’t bring your iPhone into the bathroom. Put “safe search” on for YouTube
Each man has specific parts of the body that turn us on. For some it’s breasts, for some it’s feet. For some it’s legs. Don’t gather pictures of those body parts and don’t look at pictures of them intentionally. That is inviting your sinful nature to please itself now.
As a man, I know how hard it is to control the sinful nature, especially when it comes to sexual desires. But God will give you strength, and you will succeed! I love you, son!