Why did Jesus (the son of God) come to earth?

Mathew 9:10-12
'While Jesus was having dinner at Mathew's house, many tax collectors and 'sinners' came and ate with him and his disciples. When the Pharisees saw this, they asked his disciples, "Why does your teacher eat with tax collectors and 'sinners'?"

'On hearing this, Jesus said, "It is not the healthy who need a doctor, but the sick. But go and learn what this means: 'I desire mercy, not sacrifice.' For I have not come to call the righteous, but sinners."

Does this mean Jesus did not want to save or help the 'righteous'?

No, just that unless the 'righteous' realise they are also 'sinners' they cannot be helped. Because the cross is God's sacrifice for our sin and it will mean nothing to us unless we acknowledge we are all sinners, but through faith in Jesus, our sin was transferred to Jesus who bore the penalty of all sin by dying on the cross. And because Jesus is the Son of God, and led a sinless life despite temptation, He is able to bear the sin of the world, take our punishment for us, forgive us, and allow us to share eternal life with Him in heaven and on earth. Because you enter the Kingdom of God once you believe, not once you physically die. God's Kingdom is of the spirit, and it is the spirit of love. (NB you cannot be tempted to do something if you are incapable of doing it, therefore Jesus had the freedom of choice and ability to sin but chose not to.)

So what will you do, now you know this? Will you invite Jesus into your life? Will you dare to go against the ways of living which are contrary to God? You know what they are, you don't need me to tell you. Will you dare to bear witness to your new faith despite persecution that may come? Despite ridicule? Despite condescension? Despite the lack of faith and understanding of those close to you?

The journey will not be easy. You will be tested in your faith time and time again. And sometimes you will want to give up. Know that the effort is worthwhile and no temptation has come to us other than what is common to us, to all mankind. Run your race is such a way as to win. Your race is your life on earth and the power to run it comes not through any physical or mental strength or will but through your faith in God.