That is true. In the OT a prophet (I believe) said to 'test' God. Cast your bread (money, these days) upon the waters and you'll see it return to you ten-fold (or was it seven-fold? It's been so long since I read that that I can't recall it word for word). Jesus, of course, would and in a way id, say the same about love for your neighbor since if you don't love your neighbor unconditionally, then you don't love God.