Luke 11:37-42; Matthew 6:19-24; Proverbs 3:9-10
There are lots of reasons behind tithing to support the mission of Christ, but maybe the strongest case for it is because Jesus told us to! There is a passage in Luke 11 we'll read soon that shows Jesus talking with a Pharisee (religious person). Jesus tells him that the Pharisees love to boast about their tithing in front of everyone, but they avoid other parts of following God like love and justice.
Instead of telling them to completely ignore tithing and only focus on the things they were missing, He says they ought to have continued to tithe and ALSO not neglect things like justice and love. He's letting them know that the only thing they were actually doing right was being faithful with their finances (although they were doing it with the wrong motives and the wrong heart, hence his instruction for them).
Jesus makes it clear that it wasn't just something that the Israelites did in the Old Testament, but it was something we ought to carry into the church.
Maybe the greatest reasoning for His decision to carry it over for us as Christians is because when we give, we get the opportunity to support the mission of Jesus. We get to participate in seeing people's lives changed because we can open the doors and turn the lights on.
Maybe the question shouldn't be 'why tithe,' but 'why not?' If you're truly following Jesus, why wouldn't you want to give and support people meeting Jesus just like you were provided the opportunity to?Adapted From: Next Steps Give - You Version