I saw this quote from John Piper about legalism and thought I’d share it.
[L]egalism will be present wherever a person is trying to be ethical in his own strength, that is, without relying on the merciful help of God in Christ. Simply put, moral behavior that is not from faith is legalism. The legalist is always a very moral person. In fact the majority of moral people are legalists because their so-called Judeo-Christian morality inherited from their forefathers does not grow out of a humble, contrite reliance on the merciful enabling of God.