"That's when he drank the Kool-Aid"

"That's when he drank the Kool-Aid"

From a Law and Order episode.
A friend of the defendant describing how his buddy crossed the line into extreme religious zeal.

Good one.

It is a good one, and I've been hearing it in other (quasi-religious) contexts. People who fervently buy into the rah-rah Wal-Mart Way, or some pyramid scheme like Amway. They could also be classified as religions, I suppose, if you want to see it that way....

There is a nationally syndicated talk-radio commentator who in the past has urged Senator John McCain to "lay off the Kool-Aid" when the Senator has taken a position that coincides with the Democrats' position on one matter or another.