The line comes from The Boondock Saints, the 1999 crime film following Irish brothers Connor and Murphy MacManus, who recite a family prayer before carrying out vigilante killings. The full prayer invokes shepherds acting on God's behalf, and its opening line became the most quoted part of the film. As the movie gained a cult following on DVD and online, the quote was clipped, shared and reused in fan edits, gaming videos and motivational montages, where its solemn tone still lends a sense of moral certainty to dramatic moments.