Try reading 1 Corinthians 3 again, and I mean the entire chapter:
"And so, brothers and sisters, I could not speak to you as spiritual people, but rather as people of the flesh, as infants in Christ. I fed you with milk, not solid food, for you were not ready for solid food. Even now you are still not ready, for you are still of the flesh. For as long as there is jealousy and quarreling among you, are you not of the flesh, and behaving according to human inclinations? For when one says, I belong to Paul, and another, I belong to Apollos, are you not merely human?
What then is Apollos? What is Paul? Servants through whom you came to believe, as the Lord assigned to each. I planted, Apollos watered, but God gave the growth. So neither the one who plants nor the one who waters is anything, but only God who gives the growth. The one who plants and the one who waters have a common purpose, and each will receive wages according to the labor of each. For we are Gods servants, working together; you are Gods field, Gods building.
According to the grace of God given to me, like a skilled master builder I laid a foundation, and someone else is building on it. Each builder must choose with care how to build on it. For no one can lay any foundation other than the one that has been laid; that foundation is Jesus Christ. Now if anyone builds on the foundation with gold, silver, precious stones, wood, hay, straw the work of each builder will become visible, for the Day will disclose it, because it will be revealed with fire, and the fire will test what sort of work each has done. If what has been built on the foundation survives, the builder will receive a reward. If the work is burned up, the builder will suffer loss; the builder will be saved, but only as through fire.
Do you not know that you are Gods temple and that Gods Spirit dwells in you? If anyone destroys Gods temple, God will destroy that person. For Gods temple is holy, and you are that temple.
Do not deceive yourselves. If you think that you are wise in this age, you should become fools so that you may become wise. For the wisdom of this world is foolishness with God. For it is written,
He catches the wise in their craftiness,
and again,
The Lord knows the thoughts of the wise,
that they are futile.
So let no one boast about human leaders. For all things are yours, whether Paul or Apollos or Cephas or the world or life or death or the present or the futureall belong to you, and you belong to Christ, and Christ belongs to God."
Under normal circumstances I might not copy-and-paste an entire chapter of text, but really the only way to understand what is being said in verse 16-18 (which I put in bold above) is to have at least some idea about what Paul's talking about.
Paul is talking about the community, the Church. The harm done against God's temple--the Christian Church--is the issue the apostle is addressing.
If you are looking for the "your body is a temple" passage, it's in 1 Corinthians ch. 6, vs 12-20,
"All things are lawful for me, but not all things are beneficial. All things are lawful for me, but I will not be dominated by anything. Food is meant for the stomach and the stomach for food, and God will destroy both one and the other. The body is meant not for prostitution but for the Lord, and the Lord for the body. And God raised the Lord and will also raise us by his power. Do you not know that your bodies are members of Christ? Should I therefore take the members of Christ and make them members of a prostitute? Never! Do you not know that whoever is united to a prostitute becomes one body with her? For it is said, The two shall be one flesh. But anyone united to the Lord becomes one spirit with him. Shun prostitution! Every sin that a person commits is outside the body; but the one who partakes of prostitution sins against the body itself. Or do you not know that your body is a temple of the Holy Spirit within you, which you have from God, and that you are not your own? For you were bought with a price; therefore glorify God in your body."
In several cases the NRSV has rendered the Greek word porneia (prostitution) as the familiar though archaic "fornication"; for the sake of making my point I've re-rendered "fornication" as "prostitution" and "fornicator" as "one who partakes of prostitution".
To that end it is essential to understand the sacred prostitution trade that existed in Corinth; in Corinth there existed from ancient times a temple dedicated to Aphrodite, and ancient historians (such as Strabo) how the priestesses of Aphrodite offered their services as part of the rites offered to the goddess.
To engage sexually with a temple prostitute was not merely an act of sexual indiscretion, it was to partake in the religious rites offered to another deity, and that is why St. Paul makes such a big deal about it.
This has absolutely nothing to do with smoking, drinking, or tattoos; and everything to do with engaging in what ultimately amounts to idolatry.
-CryptoLutheran