A religious billboard with a little attitude and humor aimed at Mass Pike drivers captured the attention of clandestine critics who went to great lengths to change its message with a barb of their own that looked like the original script.

Chris Kelley, station manager of three-year-old WQOM Catholic Radio, said listeners called early Thursday morning reporting that the big black billboard suggesting: “Try God,” with the text “1060 AM Catholic Radio” underneath had grown a new punch line with the words “The Other White Meat” replacing the station’s call letters.

“This is clearly not a circumstance of some teenagers with spray paint. Someone went to a lot of trouble to make it appear that the new text was a real billboard message,” said Kelley. “This act, however, is an indication that the ‘Try God’ billboard campaign is attracting attention and making people reflect on the role of God in our lives.”

The campaign has 23 billboards on major highways throughout the Greater Boston area, station officials said, and the plan is to keep them up through Sept. 22.

“An act against one faith, in some ways, is an act against all faiths, and against all people of faith, said Scot Landry, host of “The Good Catholic Life” radio program on WQOM. “This act of vandalism was certainly not a prank. It should cause us to reflect on the subtle and not-so-subtle ways that hostility is increasing against the practice of faith and against religious expression.”

Kelley said the high-wire message switch has been reported to Boston police.

“The whole point was to start a conversation,” he said of the billboard.

What the rewrite message meant, he doesn’t know. “It’s hard to speculate, it’s hard to know people’s motivation,” he said.

­— citydesk@bostonherald.com