He was disapproving of Congress spending time voting to reaffirm "In God We Trust" as the national motto.
(I don't really get the theology of it. Does the President purport to know what legislation God wants Congress to pass? And if God is big on people helping themselves, why should government intervene with attempts at help? I know... it's just a joke about God. Obama is using the Lord's name to jab at people who are using the Lord's name. I need a reading on whether God likes any of that.)