The Pharisees and their scribes complained to his disciples, saying, “Why do you eat and drink with tax collectors and sinners?”-- Luke 5:30-32
Jesus said to them in reply, “Those who are healthy do not need a physician, but the sick do. I have not come to call the righteous to repentance but sinners.”
As collaborators with the Roman oppression of the Jewish people in Palestine, and as a group that frequently collected far more in taxes from the peasantry than were actually due to the Roman state (so as to enable embezzling by themselves), tax collectors were seen as grave sinners indeed. But it was to such lost sheep that Our Lord's mission of mercy and forgiveness was especially directed. Our Lord has a special love for those of us who struggle with sin: like me and you.