Tithing (giving 10%) has become standard in the church today. Is it Biblical or just convenient to not search Scriptures and just follow routine that doesn't need much prayerful financial introspection, sacrificial giving, or trust in God's grace to work in His people? It's dangerous when we think that we can give 10% and do what we want with the rest, even though all is God's.
Proponents of tithing argue that tithing preceded the Law so it should supersede it. But this occurred only twice: Abraham tithing to Melchizedek (Gen 14) and Jacob vowing to tithe to God to preserve him (Gen 28). Both were one time vows. In Jacob's case, he had a selfish motive.
Proponents argue that OT laws should unequivocally carry over to the NT. But really, the Israelites gave more than 10%, tithing three times for Levitical, Festival, and Charity tithes. Also, these don't transfer to the NT, since the sacrificial system is fulfilled in Christ, feasts are fulfilled in Him, the Passover Lamb, and helping the poor is no longer geographically limited to Israel.
Tithing was not commanded in pre or post Mosaic Law, but required for those under it. It's no longer expected in the NT; we're now under grace. Yet we should still pay taxes. We should still voluntarily give, as free-will offerings can be seen in pre, post, and in Mosaic Law.
Giving 10% is not necessarily bad. It can be a good start, and we can ensure we give 10% yet continue to freely give above it. It becomes wrong if it squelches our generosity in thinking 10% is enough, or it leads to self-righteousness, deceives us into thinking God is pleased with our money not our obedience, or causes us not to pray over our finances.