How do I know if God wants me to stay single for life?
Singleness is a good thing. Staying single for the purposes of God is absolutely good, something that single men and women should never be ashamed of, and something that others should never make fun of. It isn't called single "blessedness" for nothing, you know.
Is it for all?
All of us are born single, and we all stay single until we get married. There are some, however, who prefer to remain single for the rest of their lives so that they can live for a great purpose. Don't get me wrong: I'm a happily married man, and in no way am I saying that singleness is better. What I am saying is that it's not a bad thing to remain unmarried.
Consider what the apostle Paul tells single men and women:
"...An unmarried man can spend his time doing the Lord's work and thinking how to please Him. But a married man has to think about his earthly responsibilities and how to please his wife. His interests are divided..." (see 1 Corinthians 7:32-34 NLT)
Single-blessedness allows a person to focus his attention to God and His plans. He can go serving the Lord every single day without the need to worry about his wife's welfare, how she is doing, and what he can and should do for her.
We all have to understand that that kind of life and purpose isn't given to all, however. Not everyone can handle being alone for the rest of their lives. The Lord Jesus Himself said in Matthew 19:11-12,
"Not all men can receive this precept, but only those to whom it is given. For there are some eunuchs who have been so from birth, there are some eunuchs who have been made eunuchs by men, and there are some eunuchs who have made themselves eunuchs for the sake of the kingdom of heaven. He who is able to receive this, let him receive it."
Pursuing God's purposes
So how do you know if you are destined to stay single for the rest of your life? I won't try to answer that question for you point by point, but I will give you just one possible clue: If you think you can.
The Lord Jesus Himself said it is only for those "to whom it is given." Paul agrees, saying in 1 Corinthians 7:7 that "every man has his proper gift from God, one after this manner and another after that," in reference to celibacy. Not everyone is designed to remain single (see 1 Corinthians 7:9).
Remember, God knew that it wasn't and still isn't good for man to be alone, especially in the pursuit of His purposes (see Genesis 2:18). God gave man a partner for that very purpose.
In conclusion, we should all realize that both single-blessedness and the married life are gifts from the Lord, and both actually enable individuals to follow Christ and pursue God's great plan. If you can stay single and remain focused on the Lord's plan without danger of falling into sin, then stay single. It's not wrong for you to marry, however – because marriage was and is God's gift to all of mankind, something that allows all who marry to pursue Him.