Simplify the following text for a Grade 13 native English-speaking person.
Original: The connection of Joseph of Arimathea with the Grail legend dates from Robert de Boron 's Joseph d'Arimathie ( late 12th century ) in which Joseph receives the Grail from an apparition of Jesus and sends it with his followers to Great Britain ; building upon this theme , later writers recounted how Joseph used the Grail to catch Christ 's blood while interring him and that in Britain he founded a line of guardians to keep it safe .
Simplified: The connection of Joseph of Arimathea with the Grail legend dates from Robert de Boron 's Joseph d'Arimathie ( late 12th century ) . In the story , Joseph receives the Grail from an apparition of Jesus and sends it with his followers to Great Britain ; building upon this theme , later writers told how Joseph used the Grail to catch Christ 's blood while burying him and that in Britain he founded a line of guardians to keep it safe .