John Gill Commentary Luke 17:33

"Whosoever shall seek to gain his life shall lose it: but whosoever shall lose [his life] shall preserve it." — Luke 17:33 (ASV)

Whoever shall seek to save his life
By fleeing to some strong hold, or by continuing in the metropolis, and strongest city in the nation, Jerusalem:

shall lose it :
there he will be in the greatest danger:

and whoever shall lose his life ;
or expose it to danger, by fleeing to the mountains, or going to Pella, a small town beyond Jordan, of no strength, and where there might be thought no security;

shall preserve it; he shall be safe; (See Gill on Matthew 16:25).