'Christians typically identify two ways to respond to God: follow him and do his will, or reject him and do your own thing. Ultimately this is true, but there are actually two ways to reject God that must be distinguished from one another. You can reject God by rejecting his law and living any way you see fit. And you can can also reject God by embracing and obeying God's law so as to earn your salvation. The problem is that people who belong in this last group - who reject the gospel in favor of moralism - look as if they are trying to do God's will. Consequently, there are not just two ways to respond to God but three: irreligion, religion, and the gospel.'
Timothy Keller, Center Church, p.63.
