Paul here shows a fatherly love in his correction of the Christian community in Thessalonica. It would seem that he is trying to deal with a tendency that was not unique to this group of believers, a yearning to tie the future that God desires for His people down to specifics of time and place and form. These early Christians apparently felt that they could and should determine what God had in store for them - and we ourselves still do it when we question exactly how the world will end (and when), whether there will be a "rapture" or not, or just what we can expect in heaven.

I believe that we can ponder and discuss such things, but in the long run all of this is only speculation - and in concentrating on this kind of details we lose sight of what is truly important: Jesus called us to forget our selves and to place our trust in Him, to follow Him wherever He goes, and to just let the Lord and His Father and Their Spirit decide, in their immense wisdom and love, what is best for us.