It is never said in so many words that we are to give 10% in the NT, though it is worth pointing out that the tithe was not original to Moses and the Mosaic law. It is found early in the life of God’s people. Abraham paid a tithe to Melchizedek in Gen. 14, if you remember. There is some case there for arguing that the tithe is basic to human life as God ordered it. But, if you are not persuaded of that, remember that if the 10th is not our rule any longer, surely in the NT we are not going to argue that we should give less! We are not going to argue that having seen the Lord on the cross, having witnessed the resurrection, knowing as we now do what price was paid for our redemption, we should give less than they did in the OT? Surely not. Jesus, remember, makes a point of calling attention to the generous gift of a poor woman when she was worshipping at the temple and Paul makes a good deal of the sacrificial financial stewardship required of Christian believers. Now, perhaps we like the tithe after all!