18 Nevertheless, “when he slew them they sought Him:” not for the sake of eternal life, but fearing to end the vapour too soon. There sought Him then, not indeed those whom He had slain, but they that were afraid of being slain according to the example of them. But the Scripture has so spoken of them as if they sought God who were slain; because they were one people, and it is spoken as if of one body: “and they returned, and at dawn they came to God”. “And they remembered that God is their Helper, and the High God is their Redeemer”. But all this is for the sake of acquiring temporal good things, and for avoiding temporal evil things. For they that did seek God for the sake of temporal blessings, sought not God indeed, but things. Thus with those God is worshipped with slavish fear, not free love. Thus then God is not worshipped, for that thing is worshipped which is loved. Whence because God is found to be greater and better than all things, He must be loved more than all things, in order that He may be worshipped.
Source: The Enarrations, or Expositions, on the Psalms (New Advent)