解释一句VOA的含义第一句不用解释,第二句才需要解释.At times,he was a good commander

解释一句VOA的含义
第一句不用解释,第二句才需要解释.
At times,he was a good commander and a brave man.At other times,he stay in the safety of the cities,instead of leading his men to fight.
"stay in the safety of the cities”,这里意思是“呆在安全的城市”,还是“呆在城里面的安全地方”,为什么不写成“stay in the safe city”?句子的意思和这个一样吗?