Aleš,
a search on six pointed star over a crescent moon turned up this
The symbol on this flag represents the Biblical quote from John 3:30 - “He must increase, but I must decrease,” spoken by John the Baptist about Jesus. Here, the waning crescent moon stands for John, and the bright star stands for Jesus.
Similar symbols appear on the flags of
- City of Oelde, Germany
- City of Niederglatt, Switzerland
- several cities in Poland