"The law was given through Moses," John writes. "Grace and truth came through Jesus Christ" (John 1:17). John saw a contrast between the law and grace, between what we do and what we are given.

Nevertheless, Jesus didn’t use the word grace. But his entire life was an example of grace, and his parables illustrated grace. He sometimes used the word mercy to describe what God gives us. "Blessed are the merciful," he said, "for they will be shown mercy" (Matthew 5:7). In this, he implied that we all need mercy. And he noted here that we should be like God in this respect. If we value grace, we will give grace to others.

Later, when Jesus was asked why he associated with notorious sinners, he told people, "Go and learn what this means: ‘I desire mercy, not sacrifice’" (Matthew 9:13, quoting Hosea 6:6). In other words, God wants us to show mercy more than he wants us to be perfectionists in law-keeping.

We do not want people to sin. But since transgressions are inevitable, mercy is essential. That is true of our relationships with one another, and true of our relationships with God, too. God wants us to know our need for mercy, and for us to have mercy toward others. Jesus was exemplifying this when he ate with tax collectors and talked with sinners—he was showing by his behavior that God wants fellowship with us all, and he has taken all our sins upon himself and forgiven us in order to have that fellowship.

Jesus told a parable of two debtors, one who owed an enormous sum, and the other who owed a much smaller amount. The master forgave the servant who owed much, but that servant failed to forgive the servant who owed less. The master was angry and said, "Shouldn’t you have had mercy on your fellow servant just as I had on you?" (Matthew 18:33).

The point of the parable is that each of us should see ourselves as the first servant, who was forgiven an enormous debt. We have all fallen far short of what the law requires, so God shows us mercy—and he wants us to show mercy as well. Of course, in mercy as well as in law, we fall short of what we should do, so we must continue to rely on God’s mercy.

The parable of the good Samaritan concludes with a command for mercy (Luke 10:37). The tax collector who pleaded for mercy was the one who was set right with God (Luke 18:13-14). The wasteful son who came home was accepted without having to do anything to "deserve" it (Luke 15:20). Neither the widow of Nain nor her son did anything to deserve a resurrection; Jesus did it simply out of compassion (Luke 7:11-15).