I disagree that not paying tithes to an assembly is a sin. I would love to see where the bible says that.
I am not getting to anything; it's just something to think about. No need to be defensive over it.
As far as why follow, I say follow Christ. The purpose of the comment I made was to say that the person one goes to for guidance is just as important as what one believes. If a person says they believe the bible to be the truth but follows someone who is not teaching truth from that bible they believe in, it's not a good thing. Just as you have said that if a person does not pay tithes to a local assembly, they are sinning. Whoever told you that lie, it would be wise to separate yourself from them. They don't know what they are talking about.
With Love,