2 Tim 3:16,17 All Scripture is inspired of God and beneficial for teaching, for reproving, for setting things straight, for disciplining in righteousness, 17 so that the man of God may be fully competent, completely equipped for every good work.
That scripture would include the Old and New testament.
the law requiring tithing was part of an exclusive covenant between God and the nation of Israel. Exodus 19:3-8 Only the Israelites were bound by that law.
The Bible states categorically that the sacrificial death of Jesus, in 33 C.E., blotted out, or abolished, the Law and with it the “commandment to collect tithes.” Colossians 2:13, 14
the Bible also shows that Christ fulfilled the Law, and God brought it to an end; so Christians are not bound by its regulations.
They do not tithe, nor are they under obligation to give any other contribution of a specified amount or at a particular time.
Paul wrote to the Christian congregation in Corinth: Let each one do just as he has resolved in his heart, not grudgingly or under compulsion.
Christians are not under the Law covenant given to Israel. Thus, they are not obliged to give a set amount to God.