Luke 18:1

Luke 18:1. And he spake a parable unto them to this end, that men ought always to pray, and not to faint;

An old writer says that many of Christ’s parables need a key to unlock them. Here, the key hangs outside the door; for, at the very beginning of the parable we are told what Christ meant to teach by it: "that men ought always to pray, and not to faint." And this is the parable: -