33 Seeing that the fear of death, that is, the ruin of our souls, menaces us, in what are we not acting, as we all are wont, from a sense of what will be to our advantage, in that we hold Him fast who assures us that He will be our deliverer from such danger, embrace Him, and entrust our souls to His care, if only that interchange is right? You rest the salvation of your souls on yourselves, and are assured that by your own exertions alone you become gods; but we, on the contrary hold out no hope to ourselves from our own weakness, for we see that our nature has no strength, and is overcome by its own passions in every strife for anything. You think that, as soon as you pass away, freed from the bonds of your fleshly members, you will find wings with which you may rise to heaven and soar to the stars.
We shun such presumption. and do not think that it is in our power to reach the abodes above, since we have no certainty as to this even, whether we deserve to receive life and be freed from the law of death. You suppose that without the aid of others you will return to the master's palace as if to your own home, no one hindering you; but we, on the contrary, neither have any expectation that this can be unless by the will of the Lord of all, nor think that so much power and licence are given to any man.
Source: Against the Heathen (New Advent)