Tithing is biblical.
Leviticus 27:30
"A tithe of everything from the land, whether grain from the soil or fruit from the trees, belongs to the Lord; it is holy to the Lord”
Tithing is simply giving the first tenth of all your income before taxes or anything else is taken out. The 10% requirement comes from the Hebrew translation of tithe, “עשר” or “ten”. When you tithe, you are making an investment into the Kingdom of God and saying to God: “I trust you to supply everything in my life.” It teaches us to always put God first in our lives.