Donald,
 
Regarding Matt 20:16 "So the last shall be first, and the first last: for many are called, but few chosen."
The best explanation I've found is in Gary Keasler's book "Secrets From the Parables" in which he says that the five groups of workers in the parable of the Householder correspond to the five ages of unsupervised mankind on earth:
 
1. Creation before the Law was given to Moses
2. Covenant after the Law was given through to John the Baptist
3. Church the age we are now in since Jesus died for our sins
4. Consecrated and Raptured believers
5. the 144,000 Jewish believers chosen in Rev. Chapter 7.
 
Groups 1 through 4 are called and five is chosen. Rev 17:14 refers to the "called and chosen and faithful" Both the called and the chosen are faithful. All ages have the goal of righteousness and the last age is the shortest and will be the last to come in.
 
I refer you to Gary's book for more details if you are interested in his interpretation of the Householder parable in Matt 20.
 
YBIC
 
Robert