Where does the Bible suggest swearing is a sin? And how does it define what words or type of words are to be considered sinful to say?
We all understand that taking God's name in vain is a sin. We are told this in the Bible directly. But I have never seen nor heard it explained how the Bible defines words as sinful to say. It seems to me that such things are defined socially by the particular community, not the Bible.
If the Bible does not define what types of words are to be considered sinful to say, then why are we to consider them as sinful to say?
That is a very good explanation, and the Bible does indeed mention it. But that would mean that these words are defined by humans. Christ wants us to take note of them so that we do not use them in order to control our tongue and not have our witness damaged.
However, where is the line? You consider "doggone it" to be the image of taking God's name in vain, which is what a euphemism is -- an image of the actual inappropriate word or phrase.
I've never understood "doggone it" as being a euphemism for taking God's name in vain. Certainly, one might say it rather than give in to the temptation to take God's name in vain, but even a simple sigh of frustration is the same as that. If you say nothing, you almost overwhelmingly must express the frustration in some manner, and so even a sigh becomes a replacement for a bad word or for taking God's name in vain.
I don't know of any example in the Bible to illustrate what I mean because the only thing that comes to mind is Michael the archangel disputing with Satan over what to do Moses' body, but I think he said that out of wisdom, not frustration.
Why does frustration require taking God's name in vain, whether in your mind or in your words? Yes, we get frustrated at times, but God is not the reason behind our frustrations and His name should not be the first thing we think of to express our displeasure.
It is true that phrases in any language can change meaning over time and a phrase that indicated something inappropriate in the past may now no longer have a bad meaning. However, what I pointed out was to simply research what a phrase currently means. You may be surprised how many phrases that you used simply because you heard them often and never thought about what the words meant, only to find out that you are saying something that Christians should not say.
Language was invented by God (Genesis 11:7). It is how we communicate with each other. The words within a language have agreed upon meaning; otherwise, we would not understand each other. As I showed, certain categories of meanings are inappropriate for Christians to use. Arguing that these are just human words does change the problem or the solution.