Mark 2:17 When Jesus heard it, he saith unto them, They that are whole have no need of the physician, but they that are sick: I came not to call the righteous, but sinners to repentance.
Jesus was invited to a feast at Matthew’s house, so Jesus, with a large group of His followers, joined them for the meal. This became a big issue because Matthew (Levi) was a non-practicing Jew, and also a Roman tax collector, and, therefore, an outlaw in the eyes of practicing Jews. And Jesus ate with Matthew and his rejected friends. The practicing Jews saw this as an opportunity to pull followers from Jesus, so they tried to cause division among His followers.
Jesus’ response to their trouble-making is recorded in this text for all time. He was doing what he came to this earth to do: remove the ravages, guilt, and condemnation of sin. He couldn't fulfill His mission without working among the guilty and condemned. His work was and is personal… it was and is up close. He must get close to those who need Him most, and those who need Him most are those who have been convinced by the “righteous” or the law that they are beyond help, that their sickness is incurable. This Physician ignores such a prognosis… and brings hope to the sin-sick.