17 But the generation crooked and embittering, “in all these things sinned yet more, and they believed not in His wonderful works”. “And in their days failed in vanity”. Though they might, if they had believed, have had days in truth without failing, with Him to whom has been said, “Your years shall not fail.” Therefore, “their days failed in vanity, and their years with haste.” For the whole life of mortal men is hastening, and that which seems to be longer is but a vapour of somewhat longer duration.
Source: The Enarrations, or Expositions, on the Psalms (New Advent)