I did a teaching this past sabbath on the 144,000 for people in my paltalk lecture. Here is an article that summarizes one interesting aspect of the talk: why are the 144,000 sealed and what is their mission?  I believe it is found in Mt 24:14.  Read on:
 
http://www.escapeallthesethings.com/gospel-preached-witness-world-by-who.htm
 
Kind Regards,

Tim McHyde
http://www.EscapeAllTheseThings.com
Sharing the Plainterpretation of Bible Prophecy since 2000