Possible meanings: 1) "Festus simply arrived in the area" or 2) "Festus arrived in the area to begin his rule." (UDB)
## he went from Caesarea up to Jerusalem ##
Possible meanings are 1) "going up refers to the importance of Jerusalem" or 2) "He went up to a higher elevation since jerusalem is located on a hill."
## brought accusations against Paul ##
This is a formal presentation of charges in court. Alternate translation: "accused Paul of violating laws,"
## they spoke strongly to Festus ##
"they were begging Festus" or "they begged Festus"
## that he might call him...so that they could kill him ##
"That Festus might call Paul...so that the Jews could kill Paul"
## might call him ##
"might send him"
## they could kill him along the way ##
They were going to ambush Paul to kill him on the way.