Two things…
First (and this is very troubling to me) why are the words of the pope so seemingly divisive? If we (who essentially are faithful Catholics) can’t understand who or what exactly he is referring to; if his words are so open to interpretation that we find ourselves upbraiding each other’s commitment to the faith on these forum boards, then the problem lies with the pope. He has stumbled in his responsibility to communicate in a manner that is understandable. And as a result, we are divided. That should not be so. The Shepherd needs to lead the flock, not confuse them.
Secondly, (in reference to CatholicGeek’s statement quoted above) it’s not that understanding never changes, nor that history is static, it’s that God’s law is eternal. The Law does not change. Truth does not change. Grave sin is still grave sin and it cannot be re-interpreted away. Interpreting the law is, of course, a necessary action when we face unanticipated change, but that doesn’t mean that the law itself changes. If that were the case, then everything we believe would be relative. That simply cannot be God’s intention for his people – that they cannot place their trust on the verities of His Word and the instructions of His Church. The Lord is my Rock and my salvation.