“What do you think? There was a man who had two sons. He went to the first and said, ‘Son, go and work today in the vineyard.’The parable itself, as are most of them, is pretty straight forward. A father with two sons sends the boys out into the vineyard to work. The first declines but later goes, while the second says he will go but does not. While we might be inclined to think poorly of both, the first ultimately does what his father wanted him to do, even though with initial reluctance. And Jesus audience, when asked, acknowledged that this first son was the obedient one.
“‘I will not,’ he answered, but later he changed his mind and went.
“Then the father went to the other son and said the same thing. He answered, ‘I will, sir,’ but he did not go.
“Which of the two did what his father wanted?”
“The first,” they answered.
Jesus said to them, “Truly I tell you, the tax collectors and the prostitutes are entering the kingdom of God ahead of you. For John came to you to show you the way of righteousness, and you did not believe him, but the tax collectors and the prostitutes did. And even after you saw this, you did not repent and believe him.
Matthew 21:28-32 NIV
And then, as he sometimes did, Jesus proceeded to make a direct application of the parable to his hearers. The first son represents those whose initial response to God's call in their lives is rejection. They are not interested in being obedient to his call, but do at some time repent and respond to his call. The second son represents those who render lip service to God, telling him they will do what he wants but in reality doing what they themselves want.
Jesus actually gets more specific, and personal, than this. The first son represents those considered as 'sinners' by the Jewish religious establishment, the tax collectors and prostitutes. The tax collectors were considered traitors because they collaborated with the Romans, while the prostitutes were simply immoral and living in disobedience to the Law. Yet both of them, along with many others, had repented and had come into the kingdom of God.
The priests and elders of the people are represented by the second son, the one whose words do not match up with his actions. These priests and elders, like so many today who claim the name of Christ, put on a show of piety, but it was just for show. At heart they are living for themselves, being unwilling to die to self and live as a part of the kingdom.
Which son are you? Are you living in obedience to the Father, our creator; or are you at best only rendering lip service? If the later, then it's still not too late to obey his call, go out into the vineyard, and get to work.