Why do you give? That is really the question.
I suppose that verse 1 is sort of a header for the whole section. I don’t understand the reward system, but I’m pretty sure that God’s reward is better than anything else I can imagine.
It’s about motive. Why do I give?
If you have been around the church much, you know that people give for many different reasons. Some have been told that they will get back more than they give. Some give so they can obtain leadership positions in the church. Some give because they feel guilty if they don’t. Some give as an act of piety, of worship.
Jesus uses almost comical exaggeration for both sides of this thing. I’ve never seen anyone blow trumpets when they gave, but I’ve seen stuff almost as egregious. And it is just as impossible to give without yourself even knowing you give. (This makes me feel a little better about adding some elements of exaggeration to my own stories.)
The whole discourse goes to our motives. In this case, it’s our motive for giving. If we want to be disciples of Jesus, if we desire to be righteous as described in this sermon, then we must get our motives sorted out.