"It says that our bodies are the temple of the Holy Spirit. How do I know what I can and can't do to my body?"
Our human nature wants to have a list of the forbidden and the allowed. The amazing thing about that is even the earliest evidence demonstrated that man could not adhere to that type of relationship with God. (See Genesis 3) We'll jump back to that in a bit but for now...
This question we received as part of "I Wish I Knew" references a verse in 1 Corinthians 6:19-20, "Do you not know that your bodies are temples of the Holy Spirit, who is in you, whom you have received from God. You are not your own; you were bought at a price. Therefore, honor God with your bodies." (BTW, in 1 Corinthians 3 Paul uses almost the identical wording "Don't you know that you yourselves are God's temple and that the Spirit of God is living in you?" but is using it in a collective manner, ie, the Church in Corinth was God's temple) Whenever we look at any verse like this we must always remember these three things: CONTEXT, CONTEXT, CONTEXT. Why was Paul saying this? Who was he saying it to? What prompted the statement? Paul was addressing a church (a collective of Christ-followers) in the city of Corinth who had embraced the message of the Gospel but who also had significant issues. If you read the entire letter, I personally think Paul was beside himself and was trying to carry thoughts so quickly and intensely, that he occasionally would jump around a bit. Two issues that Corinth was dealing with were: unity and sexual immorality. In this particular passage, Paul is addressing a bit of both. Early in chapter 6 he rebukes them for not seeking wise godly counsel to handle their disputes but rather a worldly and perhaps corrupt justice system. The Corinthian city culture and mindset were sensual and pleasure-seeking. Paul asks "why would you look to them for answers?" He then describes some of their behaviors and, in fact, points it out to the readers that they were at one time those types of people too. Paul was telling the readers, "in Christ, that is not who you are" (see verses 11 and 15).
One of the arguments that Paul was addressing was the apparent license that the Corinthians were feeling they had to do anything. But Paul says that while all things are lawful they are neither beneficial nor are Believers to be consumed by or flaunting of them. There may have been some confusion because Paul had made it clear to them that they were no longer subject to the law but the Corinthians began to flaunt, abuse and exploit that freedom.
So, I think the person asking this question may have been wanting to know something like: Can I get my ears pierced? Can I smoke? How much is too much to drink? Is it ok to drink alcohol? How far is too far sexually? Is a tattoo ok? When have I eaten too much? (ouch, were those my own toes?) In any of these questions we must first realize that if we have truly accepted the fact that Jesus has redeemed us, justified us and sanctified us then we have the Holy Spirit living in us. The very presence of God indwells us (see Romans 8:9). That Spirit desires for us the things that bring eternal satisfaction not temporal. So the question becomes what is the motive for the things we do. Clearly there are things to avoid (Galatians 5:16-21, 2 Corinthians 12:20, 1 John 2:15-17, Romans 1:29-31, Romans 13:12-14), but the motive behind behavior or action is the root of the matter.
If Scripture gave clear standards or rules on the things we can and cannot do -- both to our bodies and otherwise -- it would eliminate the need for us to be in a relationship with our heavenly Father. This was what happened in the Old Testament. The Law was given to demonstrate both man's inability to follow rules in order to be right with God and also to point to the full satisfaction that Christ was able to fulfill when he went to the cross on our behalf. That's the wonder of the Christian faith. We don't follow a list of rules, we live in a loving relationship. Our desire for any action should be to bring Him glory through that.
So for any question that asks about "what we can or cannot do as followers of Christ," ask yourself, "does this demonstrate the Spirit who lives in me?" We should also surrender consistently to the Spirit and the fruit he wishes to demonstrate will shine through (love, joy, peace, patience, kindness, goodness, gentleness, faithfulness and self control).
This week while I drove my kids to school, they asked why Deb and I don't want them saying, "Oh my gosh." Mckenzie my 10 year old soon to be lawyer and debater gave her compelling arguments why OMG was not "swearing." I said that I agreed, but that I was more concerned that she and her younger brother learn that God's name is holy and it would be unfitting for us to use His name casually or carelessly. It would not allow us to understand the honor His name should have in our lives. She said, "But gosh isn't his name". I said, "You're right, but for our family we would rather not even come close to dishonoring or carelessly using God's name. So, rather than see how close to the edge we can get, let's stay back a safe distance." The question then becomes, "How can I honor God the BEST with the things I do with/to my body?"