This passage has been used in various ways to promote things like good health and sexual purity, and to teach against things like suicide and smoking. It says: “Do you not know that you are God’s temple and that God’s Spirit dwells in you? If anyone destroys God’s temple, God will destroy him. For God’s temple is holy, and you are that temple” (1 Cor 3:16-17, ESV).
However, what cannot be seen in most English translations is that the “you” in this passage is plural in the Greek (the ESV does have a footnote at the bottom referring to this note, for those who pay attention to these things). So essentially, what Paul is saying is “you all (collectively) are God’s temple (singular),” not necessarily that you (singular) are each a temple of God. He does say something similar to this second option elsewhere (1 Cor 6:19) in relation to sexual purity, but to stay focused, I will refrain from commenting on that verse for now.
The context in which Paul makes this statement, that “we” are the temple of God, is his rebuke against the Corinthians for treating servants of Christ as celebrities. Many, evidently, argued with each other regarding who was the supreme apostle. Some argued for Paul; others for Apollos; some may have argued for Peter. Whomever the list consisted of, Paul rebukes this divisive thinking and informs them that they are all on the same team–the same house–working together to “build on the foundation” of Christ (Gk. ἐποικοδομεῖ ἐπὶ τὸν θεμέλιον). Paul commonly uses architectural metaphors to describe the building up of the church (cf. Eph 2:19-22; 4:11-12), including the phrase “build on the foundation” and the metaphor of “temple” (ναός) here in this passage. So when Paul says “you (pl.) are God’s temple (sing.),” he is actually referring to the collective group of believers, the church. And so he who destroys the temple of God destroys the church, which is why in v. 17, Paul gives the stern warning that anyone who destroys God’s temple–the church, the “household” of God (cf. Gal 6:10; Eph 2:19; 1 Tim 3:15)–through their divisiveness, will face some serious consequences.
Perhaps, the individualistic, self-absorbed Western culture that we live in has affected our way of reading texts like this. Individuals in our society may have the tendency to read or gloss over a passage of Scripture and immediately draw an individualistic application for him-/herself without much thought to its context and co-text. “How does this apply to me today?” While that is not a bad question to ask when reading Scripture, the focus in studying the Bible can become too much on me rather than we. The point of this passage is not to say that individual sins like suicide are prohibited (it is indeed prohibited, but not on the basis of this text). The point of this passage is to promote unity in the body of Christ and fight against divisiveness in this body, especially when it comes to glorifying servants of Christ. Being the temple of God, here, has everything to do with being a part of something greater than just one person. It has to do with doing your part in promoting unity in the body. It requires that we refrain from fighting against each other and indulge in fighting for unity with each other.