It is true that there are some contradictions in the Holy Bible, just like there are even worse contradictions in the Koran.

However, this contradiction is no doubt just a translation error from ancient text.  The word oinos can and does refer to either unfermented grape juice or fermented wine.

Many thus believe that it was simply grape juice being served at the wedding that Jesus attended, and not actual wine containing alcohol.

So saying that Jesus turned the water into grape juice, is the more accurate translation.

Of course, some others use this, and some other references in the Bible, to argue that drinking alcohol in moderation is considered OK by the Bible.   However, it is best for you to error on the side of caution, in order to best avoid damnation.
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