And all the tithe of the land, whether of the seed of the land, or of the fruit of the tree, is the LORD's: it is holy unto the LORD. And concerning the tithe of the herd, or of the flock, even of whatsoever passeth under the rod, the tenth shall be holy unto the LORD
Leviticus 27:30, 32

You may say, "I've been giving tithes twenty years now. How come my financial situation hasn't changed much? What is wrong?"

Look again at what this Scripture says: All the the Lord's. When you give your tithe to God, you aren't giving. You are simply returning what He gave to you. You don't get a harvest off what used to belong to somebody else.

If I let you borrow my car, and you race down the highways but bring it back all clean with no damage, I won't give you a reward. You had the reward. You drove my car. I will just thank you for returning what belongs to me.

The tithe is not a seed; there is no harvest off the tithe. The tithe just gets you in the door to the greatest financial system in the planet.