Not to mention, when tithing is preched from the pulpit it is taught from scripture in the NT that has most likely be taken out of context to suit the churches needs.
Which in turn makes me wonder how you can trust the preacher? What else do they they take out of context to meet a need? That's not to say every pastor does this. Most times they are going on a doctrine of man, taught to them from generations of wrong teaching.
That is why we must be good stewards of God's Word and know the bible, so we can feel assured that we n judge the teaching.