Isn't the "smoking is filthy, bad, disgusting, etc." talk becoming a bit redundant by now? I don't know of a single person who smokes and does not know the downside.
As to whether or not it is sin, there have been many quotes from 1Cor3:16. Of interest is when Paul uses "the Spirit of God dwells in 'you'", the "you" is humeis, which is 2nd person plural, as in "you all", not 1st person singular. He means you, Corinthians collectively.
Also the 1Cor chptr 6 version is preceded by an interesting vs, 18. "Flee fornication. Every sin that a man doeth is without (outside) the body; but he that committeth fornication sinneth against his own body." Per this verse, apparently, only fornication is a sin which we commit against our body, not smoking.
Mark 7:15 "There is nothing from without (outside) a man, that entering into him can defile him; but the things which come out of him (his heart), those are they that defile the man."
Thoughts from an ex-inhaler! BHG, I agree with you to wait on the Lord. As was with me, God in His time, by His grace took the habit away from me. Therefore ALL glory could go to him, not my *will power*.