Commentaire sur Les Psaumes 125:2

Jerusalem – Even though mountains surround her she lacks strength and the nations rule over her, conquering her one from another. And she will not have strength until the people of the Lord are within her, because then He will surround His people. Then His name will be a strength to them greater than mountains and the enemy will never again rule over them:

Jerusalem has mountains – because they stand around her, and the Lord surrounds His people within her. Therefore the enemy cannot come lay siege to Jerusalem: