Jesus uses a question to remind the person with the sword that Jesus could stop those who are arresting him. Alternate translation: "Surely you know that I could call ... angels." (See: [[rc://en/ta/man/jit/figs-rquestion]])
The word "legion" is a military term that refers to a group of about 6,000 soldiers. Jesus means God would send enough angels to easily stop those who are arresting Jesus. The exact number of angels is not important. Alternate translation: "more than 12 really large groups of angels" (See: [[rc://en/ta/man/jit/translate-numbers]])