There is huge debate in the church on whether or not tithing (giving 10% of your income) is Old Covenant, New Covenant or Pre-Covenant. I believe that Proverbs sheds light on this and refers to giving God the FIRST fruits of our wealth to God to Honor Him.
Giving is about worship. It’s a heart issue, not a financial one.
Abraham was inspired to give Melchizedek 10% of the spoils (Genesis 14:18-20) out of gratefulness, and awe of who Melchizedek was, not obligation. The word honor in the Hebrew here is one of the words used to describe the "Kabad" (weight) of Glory. Quite literally, giving is a practical way we give glory to God, as we honor him with the FIRST fruits of what we earn or possess.
I’ve known many wonderful Christians that struggle with giving, over a theological question or simple greed; but I can honestly say that in 15+ years of ministry that I don’t know anyone with chronic financial problems who is a regular cheerful tither and giver. Yes, its anecdotal evidence and I wouldn’t build my life around it, but do with that what you will.
I tell many folks to keep their money if they aren’t happy about honoring God with it. You get no points for giving under obligation. Jesus said,
"For where your treasure is, there your heart will be also." - Matthew 6:21
For all the talk and argument out there on the subject of tithing and giving, the bottom line is that if the Lord doesn’t have your money, he doesn’t have you.