I just want to ask a question. I am currently 15 years old. I was baptized recently. My question is: Is it okay for me to date someone who is not baptized or who is not in the church of Christ? I know that the Bible says in the Old Testament that if someone who was not a Jew married someone who was that it was a sin, but how does that effect us? Can I or can't I date someone out of the church of Christ and then convince them to be part of the church or not?
The ultimate purpose of dating is to find someone you would like to marry. Thus, in the back of your mind, you should be choosing dates where you see there might be a possibility of strong interest in the future. Therefore, before you actually date someone, you need to think about the type of woman you would like to marry. What are you looking for in woman? As the years progress, you will likely find yourself adjusting that mental list. You will date someone and realize there are qualities, which you had not thought about, that you just don't want to live with for the rest of your life.
But the question is: Should you restrict yourself to just dating other Christians?
You mentioned the Old Testament laws regarding non-Jews. There were restrictions, but not in the way that you think. There were seven nations that Jews were not to intermarry with. There is a detailed article that I wrote on this subject at: Mixed Marriages.
Christians don't live under the Old Testament laws and under the New Testament there are no restrictions other than not marrying someone who was divorced for causes other than fornication. However, this doesn't mean that marrying a non-Christian is a good choice. You have to remember that a non-Christian will not have the same interest in serving God as you have. This can cause conflicts. She may not have the same standards of morality as you do and might influence you to sin. "Do not be deceived: "Bad company corrupts good morals"" (I Corinthians 15:33). You need to be picky about who you date because of the potential influence they will have on you.