Katrina hit on what was supposed to be the start of this 'festival', now Isaac hits exactly 7 years later to the hour on what was again supposed to be the first day of this mockery. They were given 7 years to repent, and refused.
Katrina comes from the Greek word meaning to purify, to cleanse, Isaac means laughter. In Genesis God told Sarah that she would have a child she laughed, when the baby he was named Isaac because she laughed.
God purged New Orleans with Katrina, now He laughs at those who shake their fist at Him.

[link to www.southerndecadence.net]