Suarez is so sure of this that he does not hesitate to denounce the contrary teaching,—which is (perhaps unjustly) ascribed to Durandus, Scotus, and Gabriel Biel—as “rash and verging on error.”(173) In matter of fact the Church has formally defined that, because of concupiscence, no one, not even the justified man, much less the sinner, is able, without divine assistance (grace), to keep for any considerable length of time the whole Decalogue, which embodies the essentials of the moral law. “Nevertheless,” says the Council of Trent, “let those who think themselves to stand take heed lest they fall, and with fear and trembling work out their salvation, ... for ... they ought to fear for the combat which yet remains with the flesh, with the world, with the devil, wherein they cannot be victorious unless they be with God’s grace obedient to the Apostle, who says: ‘We are debtors, etc.’ ”(174) St. Paul, who lived, so to speak, in an atmosphere of grace, yet found reason to exclaim: “I am delighted with the law of God, according to the inward man, but I see another law in my members, fighting against the law of my mind, and captivating me in the law of sin, that is in my members,”(175) and: “Unhappy man that I am, who shall deliver me from the body of this death? The grace of God, by Jesus Christ our Lord.”(176) Surely it would be vain to expect the proud ideal of the Stoics or Pelagius’ presumptuous claim of impeccability ever to be realized on earth except by a special privilege of grace, such as that bestowed upon the Blessed Virgin Mary.(177) The Fathers follow St. Paul in describing the power of concupiscence, even after justification.(178) b) A pertinent question, closely allied to the proposition just treated, is this: Can the human will, without the aid of grace, overcome all the grievous temptations to mortal sin by which it is besieged? It is the common teaching of theologians that, without the aid of grace, man in the fallen state succumbs with moral (not physical) necessity to grievous temptations against the moral law, _i.e._ to mortal sin. This conclusion flows from the impossibility, which we have demonstrated above, of observing the whole law of nature for life or for any considerable length of time without the help of grace. If man were able to resist all violent temptations, he would be able to keep the whole law. The theological teaching which we are here expounding may be formulated in two different ways: (1) No man can overcome all grievous temptations against the moral law without the aid of grace; (2) there is no man living who is not now and then assailed by temptations to which he would inevitably succumb did not God lend him His assistance.