Christian is not a legalism but is the way of new life.

Matthew 9:9-13
Jesus said I have not come to call the righteous, but sinners.
Jesus called Matthew who was  ta collector. Jesus was having dinner at Matthew's house. many tax collectors an "sinner" came an ate with him an his disciples.
The tax collector is called Levi, and the feast is held at his house. Matthew may have been Levi's first name, as 'Peter' was Simon's.
Why?
Jesus presence in such company scandalizes the religious Pharisees. John's followers are also puzzled. Why does Jesus feast whereas John fasted? Luke gives Jesus' answer most clearly.
His radically new teaching cannot be squeezed into the mould(模子) of the old legalism.
Matthew wanted to describe Jesus is the savior of sinners, if anyone who think he is a righteous man then he won't need Jesus.
Follow me: Listened this calling, Matthew followed Jesus. To be a rich man but spiritual is poor,so he was following Jesus.
How?
Christian is not a legalism but is the way of new life to a sinner.