The parable you are talking about is called "The Parable of the Labourors in the Vineyard". The direct meaning shows that, though the Jєωs were first called into the vineyard, the gospel will be preached to the Gentiles and they will be admitted to equal privileges and advantages with the Jєωs. "Those who are last will be first and those who are first will be last" means that the Jєωs were once the chosen people of God but, because they refused to accept Christ as the Messiah, they will lose their Covenant with God - it will be the Gentiles who will now become the people of God's Covenant because they will be the ones to accept Christ.
The parable has a secondary meaning. It shows God's great compassion to man and His desire that all be saved. The hours worked refers to man's cooperation with God's grace. There are people who are faithful to God all their life. Other people lead sinful lives yet convert to God later on in their life. And still others don't convert to God until the end of their life, even up until their death bed (these are the eleventh hour workers). But just as those who were faithful all their life and sinned very little make it to heaven, so will those who repent later on in life or even on their death bed make it to heaven- because of God's mercy.
anyway I was considering being one of those workmen who worked least (just one hour)since all of them received equal pay. it is more profitable isn't it?
Although the worker who worked least still made it to heaven, he would still have to suffer in Purgatory for the hours he never worked. So it is not better to be slothful or idle in the spiritual life. You may go to heaven like the saint who was holier than you made it to heaven but the difference is, the saint went
straight to heaven and you will have to suffer a long time in Purgatory before going to heaven. Also, someone who has been more faithful to God in life will enjoy a higher degree of happiness in heaven than the sinner who converted later on in life.