Cap. IX Arg. 13 Sol: 'absolutely' does not mean without means — God provides for means and end; effects arise freely and contingently (Aquinas; Paul 1 Cor. ix. 27)
That word absolute or precise, which they hammer so often, does the adversaries no good. When God is said absolutely to have predestined, and absolutely to will the predestined's salvation, the point is not that he saves them with no means used and no conditions on men's part fulfilled. It is that of supreme mercy he looks ahead to means and end alike. He has so looked to both that the order of predestination stays certain — and once such a person is predestined, perishing and damnation are impossible — while still the effects of predestination come forth by the subject's condition and by the nature of the near causes providence set for those effects (Aquinas, ibid. art. 6): freely, contingently. So Paul, who with an eye to divine election and ordination knew he could not fall from salvation (Rom. 8:38), did not grow idle in pressing his own: he bruises his body and brings it under, lest after preaching to others he himself somehow prove a reprobate (1 Cor. 9:27). Divine election's firmness, then, leaves human diligence no spare office — for oneself or for others.
Latin
Neque quicquam juvat adversarios vocabulum illud, absolute sive praecise, quod toties inculcant. Deus enim dicitur absolute praedestinasse, et absolute velle servare praedestinatos, non quod sine ullis mediis adhibendis, aut ullis conditionibus ex parte hominum implendis, eosdem velit servare, sed quod pro summa sui misericordia tam de mediis quam de fine prospicit. De utrisque autem ita prospexit, ut quamvis ordo praedestinationis certus sit, et, posito quod talis persona praedestinetur, sit impossibile quod pereat et damnetur, tamen effectus praedestinationis producantur secundum conditionem subjecti, et secundum naturam causarum proximarum quas ad tales effectus Divina providentia ordinavit (ut inquit Aquinas, ibid. art. 6.), hoc est, libere et contingenter. Hinc Paulus, Rom. viii. 38, qui respectu electionis et ordinationis Divinae intellexit se non potuisse a salute excidere, tamen nihilo segnior evasit in salute sua promovenda, sed contundit corpus suum, et in servitutem redigit, ne quo modo cum aliis praedicavit ipse reprobus fieret, 1 Cor. ix. 27. Firmitas igitur electionis Divinae non facit ut supervacaneum sit officium diligentiae humanae, sive respectu sui ipsius sive aliorum.