Here is the ad I have referenced a few times and asked for people to hunt for in magizines. Now I at least have a digital copy thanks to Dane Ortlund for guest posting it on Justin Taylor’s blog. I would still like a paper copy if you happen to find one.
From page 5 of September 2007 issue of Backpacker; ad referenced by John Piper in a 2008 ETS talk in Providence, Rhode Island.
No Other Boast 