Simplify the following text for a Grade 6 native English-speaking person.
Original: Rau was known as a practising Christian ( and sometimes titled , `` Brother John '' , to ridicule his intense Christian position ; however , he sometimes used this term himself ) .
Simplified: Johannes Rau was a practising Christian . He was sometimes called , `` Brother John '' , to make fun of his strong Christian belief ; but , he sometimes used this term himself .