"we could no longer endure worrying about you." The word "we" refers to Paul, Silvanus, and Timothy but excludes the Thessalonian believers. (See: [[rc://en/ta/man/translate/figs-exclusive]])
## good to be left behind at Athens alone ##
"good for Silvanus and I to stay behind in Athens"
## Athens ##
a city in Achaia province which is now modern day Greece (See: [[rc://en/ta/man/translate/translate-names]])
## our brother ##
"our fellow Christian"
## no one would be disturbed ##
"no one would be troubled" or "no one would be moved"