Detective Comics #370 December 1967, DC Comics VG/F

Batman and Robin are on the trail of the Blitzkrieg Bandit, a crook who only robs a city for two days before moving onto another town. Finding him as he is just finishing a robbery of a building, Batman and Robin engage him in battle. During the fight, Batman gets a close look of the man they are after and becomes frightened, the Bandit takes advantage of this to land some punches on Batman. However, the Blitzkrieg Bandit is forced to flee when he knocks Batman into a display window causing a burglar alarm to go off.

Returning to the Batcave and changing back into their civilian guises, Bruce Wayne explains to Dick Grayson that he had recognized the Blitzkrieg Bandit as his old childhood tormentor Bart Lambert. He explains that when he was 10 years old, he was constantly terrorized by Lambert who would beat up on Bruce regularly, even chipping one of Bruce's teeth at one point. Bruce explains that eventually he decided to exercise and build up muscle so that he can defend himself against Lambert, but he never had a chance to defend himself due to the fact that Lambert had moved away before he could try to beat on Bruce again.