Matthew 9:9-13
9 And as Jesus passed forth from thence, he saw a man, named Matthew, sitting at the receipt of custom: and he saith unto him, Follow me. And he arose, and followed him.
10 And it came to pass, as Jesus sat at meat in the house, behold, many publicans and sinners came and sat down with him and his disciples.
11 And when the Pharisees saw it, they said unto his disciples, Why eateth your Master with publicans and sinners?
12 But when Jesus heard that, he said unto them, They that be whole need not a physician, but they that are sick.
13 But go ye and learn what that meaneth, I will have mercy, and not sacrifice: for I am not come to call the righteous, but sinners to repentance.
The Grace New Testament Commentary - Matthew 9:11-13
9:11-13 The festive event did not go unnoticed by the Pharisees who believed Jesus was keeping bad company. As separatists, the Pharisees could not understand why a man who claims to be the Messiah would attend a dinner like this. Their question to His disciples was, "Why does your Teacher eat with tax collectors and sinners?" Either Jesus overhears the question, or the disciples bring it to Him, for Jesus supplies an illustration in reply. He likens Himself to a physician and the people to whom He ministered as those who are sick. They need His spiritual healing and He is available to help. His remedy for wayward sinners is repentance.
By calling them to repentance, Jesus was not telling the people they had to repent to receive eternal life; He was still appealing to Israel to receive the kingdom. He was calling the nation to turn to the Messiah in repentance so that His kingdom might be inaugurated. This national repentance did not preclude the need for each individual to believe in Him for eternal life (John 6:47).