 Although his father destined John for a clerical career , according to the late 13th @-@ century Tales of the Minstrel of Reims he " was unwilling " . Instead , the <unk> continued , John fled to his maternal uncle at the <unk> Abbey . Encouraged by his fellows , he became a knight and earned a reputation in tournaments and fights . Although elements of the Tales of the Minstrel of Reims are apparently invented ( for instance , John did not have a maternal uncle in <unk> ) , historian Guy Perry wrote that it may have preserved details of John 's life . A church career was not unusual for youngest sons of 12th @-@ century noblemen in France ; however , if his father sent John to a monastery he left before reaching the age of taking monastic vows . John " clearly developed the physique that was necessary to fight well " in his youth , because the 13th @-@ century sources Akropolites and <unk> di Adam emphasize his physical strength . 
