It is a Christian thing too (hat tip to SVTCobra)
Matthew 23:23:
“Woe to you, teachers of the law and Pharisees, you hypocrites! You give a tenth of your spices—mint, dill and cummin. But you have neglected the more important matters of the law—justice, mercy and faithfulness. You should have practiced the latter, without neglecting the former.
Notice Jesus said, “You should have practiced the latter (justice, mercy and faithfulness), without neglecting the former (tithing).” The fathers argued, and rightful so, that Jesus word ends the discussion. Since Jesus said not to neglect the former—being tithing—then no believer should neglect tithing.
Reread my post. The part about tense.