What does it mean to really live?

1 Thessalonians 3:8  "For now we really live, since you are standing firm in the Lord."

Paul is expressing his great joy to the believers in Thessalonica upon receiving a report from Timothy about their continued faith and sanctification.  Paul was their spiritual mentor.  While in Athens, he could not stand the suspense of not knowing whether the seed he had planted there was growing or withering.  He sent Timothy to check in on them, since Paul was unable to go personally.

Upon receiving the good report, Paul says that now he and his team really live because the young believers' faith that he helped ignite still burns even in his absence.  I can understand him being pleased with the report and maybe sending back words of additional encouragement to them.  But to express his feelings as "now we really live" because of what is happening with them? 

I can think of a few things that might be so impactful to me that might cause me to express the same feelings Paul does, but unfortunately learning of the growing faith of a young believer is not one of them.  Don't get me wrong, I think it would be great.  But life-changing?  Maybe for them, but not for me.

All of this tells me that I don't place nearly enough importance on nurturing other believers and helping them grow in their faith.  I can't imagine there are many other things that could cause Paul to say "now we really live".  That gives me a clue as to just how high on my priority list this should rank.  It means placing this above many selfish things that currently occupy some of the top spots on my priority list.  If the feelings afterward reflect what Paul expressed, what more worthy cause could I apply my efforts toward?