to hit, strike, or scare someone violently; often used in the phrase 'beat the bejesus out of' meaning to harm severely.
From 'be-' plus 'Jesus,' euphemistically using the religious name as an intensifier. The phrase typically appears as 'beat the bejesus out of,' where 'bejesus' seems to represent one's vitality or sense of self.
This is probably the most colloquial 'be-' word still used today! 'Bejesus' has become almost a nonsense word—people say 'the bejesus scared out of me' without even thinking about it as a religious reference. It's euphemism so successful that people forget what they're euphemizing.
Complete word intelligence in one call. Free tier — 50 lookups/day.