What does Luke 18:13 mean?

Jesus comes to the second character in His parable of the Pharisee and the tax collector. The first, the Pharisee, has come to the temple to lift his eyes to God. But then he brags about his supposedly-fine character qualities and many devout deeds (Luke 18:9–12). The tax collector has a distinctly different experience.

In the New Testament, "tax collector" generally refers to a Jewish man who works for a Gentile, called a "publican," who has a contract with the Roman government. Whoever holds the contract is responsible for collecting a specific amount of money from the public for the government. They are free to charge more for themselves. They hire tax collectors from the local area to request, cajole, or demand the money. These tax collectors are also allowed to include their own fee and can become quite rich at.

Not surprisingly, the Jewish populace despise tax collectors. They work for and with Gentiles, which probably means they're unclean. They take money from good Jews for the Roman occupiers. And they demand a great deal more than the Romans ask for, sometimes becoming extremely wealthy.

This tax collector, however, recognizes and repents of his sin. Where the Pharisee was the hero of his own story, the tax collector makes God the subject of his prayer; he is merely the object on which God acts. The Pharisee tries to earn God's favor by comparing himself to others; the tax collector begs for mercy for his own sin. The Pharisee stands proud to draw the attention of other worshipers (Matthew 6:5). The tax collector stands some distance away and keeps his pleading between himself and God.

In the previous passage, Jesus showed how persistence will get the attention of authority figures, whether they be corrupt judges or God, Himself (Luke 18:1–8). Here, Jesus shows that the manner of the request matters. The humble tax collector leaves justified of his sin (Luke 18:14). Likewise, the Pharisee gets what he wants: the praise of others (Matthew 6:2).