Summa Theologica, Part I (Prima Pars) From the Complete...

Objection 1: It would seem that angels are not appointed to the guardianship of all men. For it is written of Christ (Phil. 2:7) that "He was made in the likeness of men, and in habit found as a man." If therefore angels are appointed to the guardianship of all men, Christ also would have had an angel guardian. But this is unseemly, for Christ is greater than all the angels. Therefore angels are not appointed to the guardianship of all men.

Obj. 2: Further, Adam was the first of all men. But it was not fitting that he should have an angel guardian, at least in the state of innocence: for then he was not beset by any dangers. Therefore angels are not appointed to the guardianship of all men.

Obj. 3: Further, angels are appointed to the guardianship of men, that they may take them by the hand and guide them to eternal life, encourage them to good works, and protect them against the assaults of the demons. But men who are foreknown to damnation, never attain to eternal life. Infidels, also, though at times they perform good works, do not perform them well, for they have not a right intention: for "faith directs the intention" as Augustine says (Enarr. ii in Ps. 31). Moreover, the coming of Antichrist will be "according to the working of Satan," as it is written (2 Thess. 2:9). Therefore angels are not deputed to the guardianship of all men.

I answer that, Man while in this state of life, is, as it were, on a road by which he should journey towards heaven. On this road man is threatened by many dangers both from within and from without, according to Ps. 159:4: "In this way wherein I walked, they have hidden a snare for me." And therefore as guardians are appointed for men who have to pass by an unsafe road, so an angel guardian is assigned to each man as long as he is a wayfarer. When, however, he arrives at the end of life he no longer has a guardian angel; but in the kingdom he will have an angel to reign with him, in hell a demon to punish him.

Reply Obj. 1: Christ as man was guided immediately by the Word of God: wherefore He needed not be guarded by an angel. Again as regards His soul, He was a comprehensor, although in regard to His passible body, He was a wayfarer. In this latter respect it was right that He should have not a guardian angel as superior to Him, but a ministering angel as inferior to Him. Whence it is written (Matt. 4:11) that "angels came and ministered to Him."

Reply Obj. 2: In the state of innocence man was not threatened by any peril from within: because within him all was well ordered, as we have said above (Q. 95, AA. 1, 3). But peril threatened from without on account of the snares of the demons; as was proved by the event. For this reason he needed a guardian angel.

Reply Obj. 3: Just as the foreknown, the infidels, and even Antichrist, are not deprived of the interior help of natural reason; so neither are they deprived of that exterior help granted by God to the whole human race—namely the guardianship of the angels. And although the help which they receive therefrom does not result in their deserving eternal life by good works, it does nevertheless conduce to their being protected from certain evils which would hurt both themselves and others. For even the demons are held off by the good angels, lest they hurt as much as they would. In like manner Antichrist will not do as much harm as he would wish. _______________________

Objection 1: It would seem that an angel is not appointed to guard a man from his birth. For angels are "sent to minister for them who shall receive the inheritance of salvation," as the Apostle says (Heb. 1:14). But men begin to receive the inheritance of salvation, when they are baptized. Therefore an angel is appointed to guard a man from the time of his baptism, not of his birth.

Obj. 2: Further, men are guarded by angels in as far as angels enlighten and instruct them. But children are not capable of instruction as soon as they are born, for they have not the use of reason. Therefore angels are not appointed to guard children as soon as they are born.

Obj. 3: Further, a child has a rational soul for some time before birth, just as well as after. But it does not appear that an angel is appointed to guard a child before its birth, for they are not then admitted to the sacraments of the Church. Therefore angels are not appointed to guard men from the moment of their birth.

I answer that, as Origen observes (Tract. v, super Matt.) there are two opinions on this matter. For some have held that the angel guardian is appointed at the time of baptism, others, that he is appointed at the time of birth. The latter opinion Jerome approves (loc. cit.), and with reason. For those benefits which are conferred by God on man as a Christian, begin with his baptism; such as receiving the Eucharist, and the like. But those which are conferred by God on man as a rational being, are bestowed on him at his birth, for then it is that he receives that nature. Among the latter benefits we must count the guardianship of angels, as we have said above (AA. 1, 4). Wherefore from the very moment of his birth man has an angel guardian appointed to him.

Reply Obj. 1: Angels are sent to minister, and that efficaciously indeed, for those who shall receive the inheritance of salvation, if we consider the ultimate effect of their guardianship, which is the realizing of that inheritance. But for all that, the angelic ministrations are not withdrawn for others although they are not so efficacious as to bring them to salvation: efficacious, nevertheless, they are, inasmuch as they ward off many evils.

Reply Obj. 2: Guardianship is ordained to enlightenment by instruction, as to its ultimate and principal effect. Nevertheless it has many other effects consistent with childhood; for instance to ward off the demons, and to prevent both bodily and spiritual harm.

Reply Obj. 3: As long as the child is in the mother's womb it is not entirely separate, but by reason of a certain intimate tie, is still part of her: just as the fruit while hanging on the tree is part of the tree. And therefore it can be said with some degree of probability, that the angel who guards the mother guards the child while in the womb. But at its birth, when it becomes separate from the mother, an angel guardian is appointed to it; as Jerome, above quoted, says. _______________________

Objection 1: It would seem that the angel guardian sometimes forsakes the man whom he is appointed to guard. For it is said (Jer. 51:9) in the person of the angels: "We would have cured Babylon, but she is not healed: let us forsake her." And (Isa. 5:5) it is written: "I will take away the hedge"—that is, "the guardianship of the angels" [gloss]—"and it shall be wasted."

I answer that, As appears above (A. 2), the guardianship of the angels is an effect of Divine providence in regard to man. Now it is evident that neither man, nor anything at all, is entirely withdrawn from the providence of God: for in as far as a thing participates being, so far is it subject to the providence that extends over all being. God indeed is said to forsake man, according to the ordering of His providence, but only in so far as He allows man to suffer some defect of punishment or of fault. In like manner it must be said that the angel guardian never forsakes a man entirely, but sometimes he leaves him in some particular, for instance by not preventing him from being subject to some trouble, or even from falling into sin, according to the ordering of Divine judgments. In this sense Babylon and the House of Israel are said to have been forsaken by the angels, because their angel guardians did not prevent them from being subject to tribulation.

Reply Obj. 3: Although an angel may forsake a man sometimes locally, he does not for that reason forsake him as to the effect of his guardianship: for even when he is in heaven he knows what is happening to man; nor does he need time for his local motion, for he can be with man in an instant. _______________________

Objection 1: It would seem that angels grieve for the ills of those whom they guard. For it is written (Isa. 33:7): "The angels of peace shall weep bitterly." But weeping is a sign of grief and sorrow. Therefore angels grieve for the ills of those whom they guard.

Obj. 2: Further, according to Augustine (De Civ. Dei xiv, 15), "sorrow is for those things that happen against our will." But the loss of the man whom he has guarded is against the guardian angel's will. Therefore angels grieve for the loss of men.

Obj. 4: Further, on Numbers 18:12: "Whatsoever first-fruits they offer," etc. the gloss of Origen says: "The angels are brought to judgment as to whether men have fallen through their negligence or through their own fault." But it is reasonable for anyone to grieve for the ills which have brought him to judgment. Therefore angels grieve for men's sins.

On the contrary, Where there is grief and sorrow, there is not perfect happiness: wherefore it is written (Apoc. 21:4): "Death shall be no more, nor mourning, nor crying, nor sorrow." But the angels are perfectly happy. Therefore they have no cause for grief.

I answer that, Angels do not grieve, either for sins or for the pains inflicted on men. For grief and sorrow, according to Augustine (De Civ. Dei xiv, 15) are for those things which occur against our will. But nothing happens in the world contrary to the will of the angels and the other blessed, because their will cleaves entirely to the ordering of Divine justice; while nothing happens in the world save what is effected or permitted by Divine justice. Therefore simply speaking, nothing occurs in the world against the will of the blessed. For as the Philosopher says (Ethic. iii, 1) that is called simply voluntary, which a man wills in a particular case, and at a particular time, having considered all the circumstances; although universally speaking, such a thing would not be voluntary: thus the sailor does not will the casting of his cargo into the sea, considered universally and absolutely, but on account of the threatened danger of his life, he wills it. Wherefore this is voluntary rather than involuntary, as stated in the same passage. Therefore universally and absolutely speaking the angels do not will sin and the pains inflicted on its account: but they do will the fulfilment of the ordering of Divine justice in this matter, in respect of which some are subjected to pains and are allowed to fall into sin.

Reply Obj. 1: These words of Isaias may be understood of the angels, i.e. the messengers, of Ezechias, who wept on account of the words of Rabsaces, as related Isa. 37:2 seqq.: this would be the literal sense. According to the allegorical sense the "angels of peace" are the apostles and preachers who weep for men's sins. If according to the anagogical sense this passage be expounded of the blessed angels, then the expression is metaphorical, and signifies that universally speaking the angels will the salvation of mankind: for in this sense we attribute passions to God and the angels.