Second difference: absolute premotion against relative delight
Thesis LXXV. Next, in the Thomists' view the physically predetermining aid is such that, whatever the circumstances in which the will is placed, it always makes it act, produces its effect, and overcomes all resistance. If the same aid that moves and determines this or that person to act well were given to everyone else, it would move them all alike, and would move this same person too, whatever impulses of concupiscence he were supposed to be shaken by.
In Jansenius's sense, however, Christ's efficacious aid works otherwise. The victorious delight in which he places that aid is relative: it is victorious only when it is greater than the opposing delight. If the other delight happens to be more ardent, the mind will cling only to ineffective desires and will never effectively will what ought to be willed.
So a delight that wins in one person, because the impulses of concupiscence are weaker, will be overcome and prove inefficacious in another, because the impulses of the same concupiscence are more violent. Nor will what is enough for this person to overcome a present temptation be enough at another time, if a stronger and fiercer temptation presses on him.
Latin
LXXV. Deinde juxta Thomistarum mentem, auxilium Physice praedeterminans tale est, ut in quibuscunque circumstantiis voluntas collocetur, semper faciat facere, & operetur effectum suum, omnemque superet resistentiam. Nempe si idem auxilium, quod hunc vel illum hominem ad bene operandum movet & determinat, reliquis omnibus daretur, omnes similiter moveret, adeoque hunc ipsum quibuscunque supponeretur concupiscentiae motibus agitatus. Verum, ex Jansenii sensu, aliter se habet Christi adjutorium efficax. Nam delectatio victrix, in qua adjutorium illud collocat, relativa est. Tunc enim est victrix quando delectatione opposita major est. Quod si contingat alteram ardentiorem esse, in solis inefficacibus desideriis haerebit animus, nec efficaciter unquam volet quod volendum est. Proinde quae in uno victrix est, propter debiliores concupiscentiae motus, in alio superabitur & inefficax erit, propter motus ejusdem concupiscentiae vehementiores. Nec quae in hoc homine ad vincendam praesentem tentationem sufficit, sufficiet alio tempore, si fortior & acrior urgeat tentatio.