The reference is as old as the hills, but it was one that touched a nerve about guns and left Jay Feely, the former NFL player turned CBS commentator, doing a little explaining Sunday morning.

At issue was a photo the former kicker tweeted Saturday night. In the usual prom night snapshot, he is standing between his daughter and her boyfriend — with one arm around his daughter and the other holding a gun at his side. “Wishing my beautiful daughter and her date a great time at prom. #BadBoys,” he wrote.

The responses on social media were swift and critical enough that he tweeted Sunday that the picture was “obviously intended to be a joke. My [d]aughter has dated her boyfriend for over a year and they knew I was joking.

“I take gun safety seriously (the gun was not loaded and had no clip in) and I did not intend to be insensitive to that important issue [of responsible gun ownership].”

Never mind that fathers have joked about this ever since, well, fathers have been having daughters, the timing of it sparked debate. Here’s a look at the image:

And here are some of the comments:

Feely, 41, played for the Falcons, Giants, Dolphins, Chiefs, Jets, Cardinals and Bears over 14 NFL seasons. Upon his retirement in 2014, he joined CBS. A spokesperson for CBS declined comment when reached by The Post.

Feely made headlines earlier this year when he revealed that Gisele Bündchen tried to get him to convince New England Patriots quarterback to retire last spring. Feely and his family are friends of Brady and Bundchen, dating back to the time when Feely and Brady were at the University of Michigan.

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