You cannot make a case that tithing is required for Christians in a legal sense. However, the principal remains the same. God supplies our salvation and all our needs. God is our source - we reflect that in our giving.
We live in a spiritual world. What we do is noticed by spiritual entities both good and evil. If we do not support our church, then you are making a statement to the heavenlies - I can make it on my own! I can just tip God and all will be well.
Matthew 6:21 LEB
For where your treasure is, there your heart will be also.
Malachi 3:8–10 LEB
Will a human dare to rob God? Yet you are robbing me! And you say, ‘How have we robbed you?’ In the tithes and the contributions! You are being cursed with a curse, for you are robbing me, the whole nation of you! Bring the whole tithe to the storehouse, so that there will be food in my house, and test me please in this,” says Yahweh of hosts, “if I will not open for you the windows of heaven, and pour forth for you an overflowing blessing.
Giving is true having, as the old gravestone said of the dead man, “What I spent I had, what I saved I lost, what I gave I have.”
John Ploughman’s Talk, Page 147