Adam Clarke on Hebrews 13:14

For here have we no continuing city - Here is an elegant and forcible allusion to the approaching destruction of Jerusalem. The Jerusalem that was below was about to be burnt with fire, and erased to the ground; the Jerusalem that was from above was that alone which could be considered to be μενουσαν, permanent. The words seem to say: "Arise, and depart; for this is not your rest: it is polluted:" About seven or eight years after this, Jerusalem was wholly destroyed.