The old spiritual about God troublin' the waters could be a good one for today's first reading. It's the antithesis of the Exodus event (you could say it was the Introit to Israel's Exodus): Israel is now leaving the desert and crossing the water into the Promised Land. Like the waters of the Red Sea, the waters of the Jordan River stop short in the presence "of the Lord of the whole earth," symbolically stationed in the riverbed by means of the Ark of the Covenant. As soon as the bearers of the Ark step foot into the Jordan, its southbound waters disappear, while the incoming flow builds up ever northward, and the people make their way dry-shod just as their parents did 40 years earlier.
Nature itself responds to the presence of the Lord. The one thing God deserves the most from us is responsiveness; sensitivity to his presence. Yet this seems to be what has become the most dulled in our hearts and minds. We seem to anticipate from God the hardness of heart we find in ourselves (as mirrored so chillingly in today's Gospel of the forgiven-but-unforgiving servant). Expecting only judgment, do we shield ourselves from God's presence? How can we begin to peek around that defensive shield and take the risk of recognizing and receiving God's love, whatever our situation?