I have a hub called "Tithing, Giving and Alms" that gives scriptural confirmation that we are not commanded to tithe under the New Covenant. Because we love God, we support not only our pastors and ministries, we also give to help others.
God expects us to provide for our own families, paramount to financially supporting the church and others. He also expects us to pay back our parents and grandparents, honoring them in this way. The religious leaders of Jesus' day had "changed" the commandment of honoring your father and mother to say the parents should accept that the money owed them had been given to the synagogue. Jesus rebuked this!
Any church that demands tithing is sinning against the New Covenant of Jesus Christ. If a believer feels so led to commit a percentage of his/her income to the church and even give to other ministries or people, they must do so without neglecting the needs of their own flesh and blood. God calls those who do not follow this ordinance "worse than heathens".
When we give as the Holy Spirit leads, God is faithful to provide for us, and proves this again and again. Money-hungry prosperity teachers, however, are abusing this promise of God to appeal to the wicked, whose motive is to give in order to receive.