I have a question on how God forgives besetting sin. I have given my life to Christ about a year ago, and it has been the best thing I could have ever done with my life. However, I’m finding myself with a pattern of committing sin. I have gone through some periods of time where I wouldn’t smoke, drink, or even masturbate. But recently I have broken my promise to not do the things again.
If I repent, does that mean that I am fully forgiven? I understand that I need to commit to not doing these things anymore, but at its base, am I forgiven? It causes me to worry because I do want to be a better follower of God. And I don’t want God to be disappointed in me.
How do I fully stop doing these things? Once I think I’m good, I find myself committing sins that I said I wouldn’t.
A "besetting sin" refers to a constant problem or fault. What you describe is difficulty in breaking the habit of past sins.
Every sin can be overcome. "No temptation has overtaken you but such as is common to man; and God is faithful, who will not allow you to be tempted beyond what you are able, but with the temptation will provide the way of escape also, so that you will be able to endure it" (I Corinthians 10:13). There is no sin that is unique to you, no sin that you can't refuse, and no sin that boxes you in so that you must sin. It doesn't mean it is easy.
You listed smoking as a problem. I don't know if it is tobacco or marijuana that you are smoking. First, we note that there is no physical need to smoke. You are able to survive if you don't smoke. Addictive substances give the impression of solving a particular problem while simultaneously contributing to the problem. People often tell me they smoke to calm their nerves, yet both tobacco and marijuana increases anxiety and nervousness as you withdraw from the drug. This sets up a spiral of depending on a drug to adjust your mood.
One way to break the spiral is to find other ways to calm yourself. It also helps to make the drug difficult to start using without thinking. Don't keep cigarettes in your home. Don't keep a lighter around. Making the habit impractical gives you a chance to get past the cravings.
Alcohol is a similar type of problem, though the reason for using alcohol is often depression. Like the smoking problem, alcohol numbs you for a while, but as it leaves your system it leaves you feeling more depressed.
While you list masturbation as the third problem, I suspect that the real problem is pornography. The drive to relieve yourself is physically necessary for males, but pornography is a sinful way to get yourself aroused. The typical reasons for using pornography is lust, loneliness, or to relieve stress. Of course, pornography doesn't cure lust -- it increases it. It doesn't solve loneliness -- it disconnects you from relationships. It does relax a male after ejaculation, but the effect is only temporary and doesn't deal with the causes of the stress. And oddly, since the Bible doesn't condemn masturbation by itself, that temporary stress relief could be had without sin.
Another problem is that you are promising God not to sin. Sin is wrong, regardless. Your promises don't change this. The promises have no meaning, but you think you've done a greater sin and condemn yourself more. As Jesus said, "But let your statement be, 'Yes, yes' or 'No, no'; anything beyond these is of evil" (Matthew 5:37). Promises are unnecessary.
When you repent of sin, it means you realize the behavior is wrong and you are committed to not accept sin in your life (II Corinthians 5:10-11). God also requires that you confess to Him your sins. "If we confess our sins, He is faithful and righteous to forgive us our sins and to cleanse us from all unrighteousness" (I John 1:9). The fact that God is faithful means we can absolutely rely on His word. The problem is not God but whether you believe God.