The guards did not believe that Jesus was a prophet. Rather they believed that a real prophet would know who hit him even if he could not see it. They called Jesus a prophet, but they wanted to show that he was not a prophet. AT: "Prove that you are a prophet. Tell us who hit you!" or "Hey prophet, who hit you?" (See: [[rc://en/ta/man/translate/figs-irony]])
"Speak words from God!" The implied information is that God would have to tell Jesus who struck him since Jesus was blindfolded and could not see. (See: [[rc://en/ta/man/translate/figs-explicit]])