Matthew 23:23 and Luke 11:42 are the verses where Jesus mentioned about tithing:
"Woe to you, teachers of the law and Pharisees, you hypocrites! You give a tenth of your spices — mint, dill and cumin. 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.” Matt 23:23 (NIV).
"Woe to you Pharisees, because you give God a tenth of your mint, rue and all other kinds of garden herbs, but you neglect justice and the love of God. You should have practiced the latter without leaving the former undone.” Luke 11:42 (NIV).
Jesus commented about tithing when he reprimanded the teachers of the law and Pharisees of neglecting the more important aspects of the law such as, justice, mercy and faithfulness. Did Jesus tithe? Of course he did because he was a devout Jew and from the above verses quoted he said tithing should not be neglected.
Tithing is not a law for Christians but it is a good guide for our giving to the Lord’s work. Our motive of giving tithe should be of worship and gratitude and not bargaining with God. Jesus spoke more often about giving than tithing, and giving in much larger amounts, including service. In Matthew 10:8 he says, "Heal the sick, cleanse the lepers, raise the dead, cast out devils: freely you have received, freely give."
“Woe to you, scribes and Pharisees, hypocrites! For you tithe mint and dill and cummin, and have neglected the weightier provisions of the law: justice and mercy and faithfulness; but these are the things you should have done without neglecting the others.
Notice Jesus said, “You should have practiced the latter (justice, mercy and faithfulness), without neglecting the former (tithing)….