What does John 18:18 mean?
Peter and John have followed the band of men who arrested Jesus (John 18:15–17). They gained access to the courtyard through John's connections with the high priest's family. They're attempting to keep a low profile, however, so they are not themselves arrested (Matthew 26:58). At least one person has already been suspicious of Peter, either recognizing his face or being suspicious of his Galilean accent (Matthew 26:73).This statement sets up a return to Peter's story later in this passage (John 18:25). If this scene were part of a modern movie, the scene would jump to Jesus' conversation with the priests inside (John 18:19–24) before jumping back to Peter here at the fire (John 18:25).
John 18:15–18 includes the first of Peter's predicted denials of Christ (John 13:36–38). Peter has followed the party who arrested Jesus, obviously at some distance, attempting to secretly see what will happen. Though Peter was brave in attempting to defend Jesus earlier, he shrinks in the face of danger here. Asked to admit his relationship with Christ, he lies. The unnamed disciple here is probably John, who may have been a relative of the priestly family.
Jesus is secretly, quietly arrested in the garden of Gethsemane and taken to a series of sham trials before Jewish leadership. This leads to His encounter with the local Roman governor. Jesus accepts being described as "King" but denies that His current purpose is earthly rule. A mob assembled by Jesus' enemies reject Pilate's attempt to free Jesus. In the meantime, Peter fulfills Christ's prophecy about a three-fold denial.