In Mal 3:10 God was describing the insurance policy of the believer. His instructions were that the tithe serves as an insurance policy against the devices of the enemy. God says that as we minister the tithe unto Him, He will cause such a rain of the blessing to come upon us that we will not have room enough to contain it. In Mal 3:11 He says that the enemy will be rebuked for the sake of the tither.
Friend, tithing has not passed away. Abraham paid tithes - Gen 14:19-20 - and it is unto the blessing of Abraham that we are called unto - Gal 3:13-14. Your tithe is not based on what is left over. Rather it is the first tenth of all of your income. Irrespective of your income level your bills and expenses should never take the place of your tithe. God instructs us to pay this tenth in order that the remaining 90% can be insured and blessed.
You must make a decision to be committed to paying your tithe. Then you can enjoy complete divine insurance over your affairs.