@BongoJo
The trouble is the old testament was written in Hebrew and the new in Greek. It seems unlikely they would use the same system. (It also sounds suspiciously like you're alluding to Roman numerals where L is 50 not 5000, and I can't see an "L" equivalent in Greek or Hebrew that has the value 5000.) It's possible this mistake happened when it was translated into Latin, but its more likely that what happened was distorted before it was recorded - much as rumours mutate today. The bible is "entertaining" gossip not factual accounts.