Berkowitz, who shot and killed six people during a yearlong spree in New York City in the 1970s, told the Daily News that society must take "the glory out of guns."
"Young people have no business carrying a gun," said Berkowitz, now 59, from his cell at the at the maximum-security Sullivan County correctional facility in Upstate New York. "I would love to speak bluntly to those gangbanging teens and wanna-bes and tell them prison is nothing like what you think. If you're packing a gun, you're making a big mistake, and you'll regret it."
Dubbed the ".44 Caliber Killer" for the gun he used, Berkowitz was arrested at his Yonkers home on Aug. 10, 1977, after terrorizing New York City over 13 months, killing six people and shooting seven others.
He later claimed his neighbor's dog ordered him to carry out the murders, The Associated Press reported.
But Berkowitz appears to have undergone a spiritual transformation since then.
He's now a born-again Christian and says he rejects violence. His "dark days," as he calls them, came at a time when he was "lost," "tormented" and "confused."
Berkowitz told the Daily News he doesn't like to talk about that time.
"It's too painful," he said. "I continue to pray for the victims of my crimes. I do wish them the best in life. But I'm sure the pain will never end for them. I regret that."