Can something be a sin to one person but not to another?
For example, one person believes our body is our temple and drinking alcohol is a sin. Another person enjoys drinking beer. Would drinking be a sin for the first person but not the second?
Another example: One person believes you should only pray to God while another person prays to saints, or to guardian angels. Would praying to another besides God be a sin if the first person did it, but not a sin for the second person?
Third example: One person believes Saturday is the Sabbath. Another person worships on another day, say Sunday. Would worshiping on Sunday (and not on Saturday) be a sin to the first person but not to the second?
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I guess what I'm getting at is this: Is sin an absolute standard? Or does it depend upon one's own standards?
The bible talks about this, using the example that a vegetarian thinks it's wrong to eat meat, and a person who eats meat does not think it's wrong. It says to let the vegetarian do that onto God for his conscience' sake, and not to eat meat in front of him if it bothers his conscience.
To those who never even seen a bible, it says that their conscience serves as a law onto themselves. (To those who
can read a bible and understand it, yet
refuse to, they are guilty of disobeying every scripture they refused to read). For the Bible says "He who
knows the good he ought to do, yet
chooses not to do it, sins." So yeah, it is possible to not know something is a sin. But we are not found guilty of that sin unless we know it is a sin before we do it. This is why Satan asked Eve if God really said not to eat of the fruit- to incriminate her. In this way, it is possible for it to be a sin to one and not
counted as sin to another.
But don't cause your brother to stumble. For example, we know it is not wrong to drink alcohol, it's only wrong to get drunk (I think alcohol is disgusting, but to each their own). But if any alcohol at all bothers your brother's conscience, don't drink it in front of him. Or if you have a known alcoholic over for dinner, you should not only not drink it in front of him, but put it out of his sight before he arrives.
NOTE: About vegetarian / vegan Christians... The Bible calls them 'weaker brothers'. For if they were strong in the scriptures they would know that God Himself prophesied in Genesis that He will one day give us every creature for food- just as He gave us the green herb. Not that we have to eat every creature, just that it would no longer be religiously wrong. And during the Old Testament feasts, God commanded that they eat from the flock and from the herd. I asked a vegan "Is it wrong to eat fish?" He answered "yes." Jesus ate fish, and He never sinned. Not only that, He lived under the old law (before He changed it)- which means He ate from the flock and from the herd.
So they might feel that it is wrong, but it is not wrong,
if it's life-blood is cooked out of it. BUT what they cannot do is force on others the burden of also refraining altogether just because they do. Tell them there's no verse for that. I had a 'no alcohol' one be so rediculous that they told me it's wrong to eat at a restaurant that serves alcohol, or even go to a grocery store that sells alcohol. They called it "an appearance of evil." They cannot force the laws of their own consciences onto other people. They need to show you a scripture stating that it's wrong.