Lk. 10:27-29

"And (the lawyer), answering, said, 'You shall love the Lord your God will all your heart, and with all your soul, and with all your strength, and with all your mind; and your neighbor as yourself.' And (Jesus) said to him, 'You have answered right; this do, and you shall live.' But he, desiring to justify himself, said to Jesus, 'And who is my neighbor?' "

This lawyer was not a particularly evil guy, and Jesus himself testified that he understood the law. But the lawyer's first thought was, "Yeah, I know the law, but how can I prove that I do it?" So his question to Jesus really was, "Who can I exclude as my neighbor, thereby justifying my failure?" I do this all the time. He (and I) would be better off just responding, "I can't do it."