As far as it goes?

Does "as far as it goes" mean "for the current situation"?
Plus, does "that takes religion" mean "it takes on the form of religion"?

Context:

Dyson partially disagrees with the famous remark by his fellow physicist http://en.wikipedia.org/wiki/Steven_Weinberg that "With or without religion, good people can behave well and bad people can do evil; but for good people to do evil—that takes religion."^{http://en.wikipedia.org/wiki/Freeman_Dyson#cite_note-nyrb06.html-59}

Weinberg's statement is true as far as it goes, but it is not the whole truth. To make it the whole truth, we must add an additional clause: "And for bad people to do good things—that [also] takes religion." The main point of Christianity is that it is a religion for sinners. Jesus made that very clear. When the Pharisees asked his disciples, "Why eateth your Master with publicans and sinners?" he said, "I come to call not the righteous but sinners to repentance." Only a small fraction of sinners repent and do good things but only a small fraction of good people are led by their religion to do bad things.^{http://en.wikipedia.org/wiki/Freeman_Dyson#cite_note-nyrb06.html-59}