Simplify the following text for a Grade 10 native English-speaking person.
Original: Longinus is the name given in medieval and some modern Christian traditions to the Roman soldier who pierced Jesus in his side with a lance , the `` Holy Lance '' ( lancea in the Latin Vulgate ) while he was on the Cross .
Simplified: Longinus is the name given in medieval and modern Christian traditions to the Roman soldier who pierced Jesus in his side with a lance while he was on the Cross .