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Five decades of consistent tithing proves Malachi 3:10 to be true for us. Yes, we encountered financial struggles, but were never without food, shelter or clothing. God is so faithful to fulfill His promises and you can take that to the bank! (Pun intended!)
There are believers who have never tithed who have testimonies of how blessed they've been of God. I'm sorry, but giving a certain amount of money to the work of the church won't keep your house from burning down. It won't keep your sons and daughters from an early death or from going to prison.
Please read the book of Job. Job was an "upright and blameless" man. He lost all of his children in one storm. Then read in Genesis the life of a boy named Joseph. His father, Jacob, grieved for years because he thought his son had been killed by a wild animal. The only thing his other sons brought to him was a bloody coat (Genesis 37). He must have thought the wild animal ate his son, no body was found. Joseph wasn't dead he was in prison. Who sinned, Jacob or Rachel, that their boy was taken from them like that? No answer is necessary...
It's a good thing to give God glory for the life we live. But, we didn't EARN that good life by giving or tithing. I've heard some churches teaching untruths like that for as long as I can remember. God is good to the just and the unjust (Mt 5:45). He's just good. (Lest anyone would boast of getting blessed because they were good). God is great and greatly to be praised... 1Chr 16:25.
It is God who works in you both to will and to do for His good pleasure (Phil 2:13). If you do anything good it's because He is in you causing you to do it. That's the blessing, even if your house burns down.