Question:i'm going to see my girlfriend and I'm kind of in a bad predicament because she wants me go to worship service with her on Sunday, but she is Pentecostal and they teach false doctrine. Is it ok for me to go so I can I can show her what is doctrinally wrong with her church and how it doesn't match what is taught in the Scripture? She also said that if I go with her, she will go with me to my church, but I think it may be a sin to even go to hers just to find out about them. And if it is a sin to go even for that reason, what do I tell her parents and her because her dad will be mad at me for sure if I tell them i can't go because I believe it is a sin to go there. I know they are sinful because denominations are wrong. I feel like if I don't go just once she will never believe me and then not attend with me because she will feel like I think I'm right and she's wrong on everything. I really need some advice on this as soon as possible. Thanks a lot!
Without getting into all the why's and wherefore's, let's use one simple example. Do you need to take a drug before you can explain to a drug user why using drugs are wrong? I hope you see that the answer is obviously, "Of course not!" It is a false argument to claim you must personally experience something before you address whether it is right or wrong.
For this same reason, you can discuss with your girlfriend whether it is right or wrong to use instrumental music in worship without having to attend. You can discuss whether the Holy Spirit still bestows miraculous gifts today without having to see a person babbling while claiming to speak in a tongue.
If you want to go because you are curious, just ask if there is service you can observe that doesn't conflict with your own worship. You ought to attend worship at your church because that is what you owe to your Lord and your brethren. "Let us hold fast the confession of our hope without wavering, for He who promised is faithful. And let us consider one another in order to stir up love and good works, not forsaking the assembling of ourselves together, as is the manner of some, but exhorting one another, and so much the more as you see the Day approaching" (Hebrews 10:23-25). You shouldn't let anything get in your way of offering acceptable worship to God. "He who loves father or mother more than Me is not worthy of Me. And he who loves son or daughter more than Me is not worthy of Me" (Matthew 10:37). I believe you can safely add girlfriend to that list.
But more important, you need to sit back and do some serious thinking. Numerous studies have shown that when two people of different religious faiths marry, there is a strong probability that they will divorce -- usually when they start having children. Many couples compromise by him going to his church and she to her church, but once the children come then there are arguments over which church the kids are going to attend. Even when the marriage survives, the children often grow up with no belief because of the constant contradiction between mom and dad. So my question for you is, should you be dating a girl with whom you cannot agree about such basic ideas regarding the Bible?
Yes, it is possible that you might change her mind. It is also possible that she might change your mind. But if, during the time you both are trying your hardest to impress the other person, you both remain in disagreement, what makes you think you will come to agreement after marriage? If stating that you find Pentecostalism wrong for reasons x, y, and z in the Bible is going to get her parents mad at you, what makes you think it is going to calm down after you get married?
Marriage is about two people becoming one in life. If you start out separate on various issues, how are the two of you going to become one?