I understand about giving in the proper spirit and with a sincere heart.
What I'm having difficulty understanding is exactly what it means to give "as God has prospered you." How much is that? What proportion of our increase should be given back to God? How do we decide that?
Does God get a piece of what's left after we pay all the bills? What piece?
This is not about the gross or the net. This is not about whether we should give back to God. This is about the definition of "as God has prospered you."
It just seems inconsistent to me to hold that God required 10% from the Jews, but is silent about us Gentiles. I somehow can't see God as saying, "Don't worry about it, just give what makes you happy. Just as long as you're sincere, I don't care how much it is. Even if it's just a dollar, I'll be happy."
One can label tithing as legalistic, but it is the one guideline we have for interpreting "as God has prospered you."