Let me see, how did that line go from that old TV show?
Warning! Warning! Danger, Will Robinson!
This man is a drug addict. He's told you that in a number of different ways. He uses alcohol and prescription medicines to numb his pain. He lost his driver's license (the typical cause of losing a license is driving under the influence, usually repeatedly). Given that, we can guess that he lost his good paying job due to poor performance due to his drug habit. His wife likely divorced him because of the drugs. If he is looking at a jail sentence, then it means he has been involved in some crime. A citizen can't sue another citizen and get the person imprisoned. Only the government can do that. So if his ex-wife is involved in this, then she is pressing charges against him through the prosecutor's office for something he did which was criminal against her or the kids. So we're not talking about a lack of child support payments.
The problem is that your a good man. You keep your thoughts pure and think the best of those around you. "To the pure all things are pure, but to those who are defiled and unbelieving nothing is pure; but even their mind and conscience are defiled" (Titus 1:15). A drug addict is a compulsive liar; they have to be to do their drugs. You can't trust anything he says because you can't tell which parts he is telling you is true or false, and that's hard for a Christian because we are used to dealing in constant truth.
Please don't ignore any of this. I'm telling you this from years of experience dealing with drug addicts. They can be some of the sweetest, nicest people you know -- so long as you don't get between them and their drugs. This is not something I would ever ask a teenager to handle.
Since you said you would come over tonight, I'm not going to ask you to break your word, but I insist that you find an adult male to go with you -- such as the preacher or your dad -- someone to help you talk to this man and to protect you from danger just by being there. The potential for danger is very high. The minimum is him offering you or slipping you a drug, which he'll justify in his mind as giving you some help to relax. Worse, he might try to come on to you. I rather you be defensive and be completely wrong, but experience tells me I'm not.
Thanks for the last message. Well, it turns out you were right. That night I went to his house I saw him smoking marijuana. But I'm not sure how to deal with this, so any advice would help. Furthermore I'm against giving money to him since I don't know what he's spending it on. But it's not like I don't want to help him. I remember Jesus saying that you should clothe your neighbor when he's in need, and also to provide him with shelter and lift his burdens. Of course this was said in various parts of the Bible as I recall, but, well, I'm not sure how to help him. At the same time part of me just wants to forget about all this because it seems like such a hassle. I don't know. What is your view on this?
You are looking at this backwards. You're confusing this man who chooses to use drugs with people who because of circumstances out of their control are facing hard times. For example, I might feel sorry for a man who is low on food because he is too lazy to work, but I'm told that he needs to face the consequences of his choice. "For even when we were with you, we commanded you this: If anyone will not work, neither shall he eat" (II Thessalonians 3:10). It is a lesson you need to learn because one day you will be a father and your children are going to make choices that you warned them against. One of the toughest things about being a parent is letting your child face the consequence of their own making. Because if you rescue them, they will repeat the error and get worse.
Hard as it might seem, this man is in his current predicament because of his own choices. The limit you can do is urge him to get into a drug rehabilitation program. Until he gets sober and wants to stay sober, there isn't anything any of us can do for him. This is exactly what I do for the drug addicts I run across. I've tried a few times to help someone without the rehabilitation and every time it has failed because a drug addict must be constantly monitored for months before their habit is broken enough that the possibility of surviving without using drugs is possible.

