Whether to the words, "Thou shalt love the Lord thy God with thy whole heart," it was fitting to add "and with thy whole soul, and with thy whole strength"?
Objection 1: It would seem that it was unfitting to the words, "Thou shalt love the Lord thy God, with thy whole heart," to add, "and with thy whole soul, and with thy whole strength" (Dt. 6:5). For heart does not mean here a part of the body, since to love God is not a bodily action: and therefore heart is to be taken here in a spiritual sense. Now the heart understood spiritually is either the soul itself or part of the soul. Therefore it is superfluous to mention both heart and soul.
Objection 2: Further, a man's strength whether spiritual or corporal depends on the heart. Therefore after the words, "Thou shalt love the Lord thy God with thy whole heart," it was unnecessary to add, "with all thy strength."
Objection 3: Further, in Mat. 22:37 we read: "With all thy mind," which words do not occur here. Therefore it seems that this precept is unfittingly worded in Dt. 6.
On the contrary stands the authority of Scripture.
I answer that, This precept is differently worded in various places: for, as we said in the first objection, in Dt. 6 three points are mentioned: "with thy whole heart," and "with thy whole soul," and "with thy whole strength." In Mat. 22 we find two of these mentioned, viz. "with thy whole heart" and "with thy whole soul," while "with thy whole strength" is omitted, but "with thy whole mind" is added. Yet in Mark 12 we find all four, viz. "with thy whole heart," and "with thy whole soul," and "with thy whole mind," and "with thy whole force" which is the same as "strength." Moreover, these four are indicated in Luke 10, where in place of "strength" or "force" we read "with all thy might." [*St. Thomas is explaining the Latin text which reads "ex tota fortitudine tua" (Dt.), "ex tota virtue tua" (Mk.), and "ex omnibus tuis" (Lk.), although the Greek in all three cases has {ex holes tes ischyos}, which the Douay renders "with thy whole strength."]
Accordingly these four have to be explained, since the fact that one of them is omitted here or there is due to one implying another. We must therefore observe that love is an act of the will which is here denoted by the "heart," because just as the bodily heart is the principle of all the movements of the body, so too the will, especially as regards the intention of the last end which is the object of charity, is the principle of all the movements of the soul. Now there are three principles of action that are moved by the will, namely, the intellect which is signified by "the mind," the lower appetitive power, signified by "the soul"; and the exterior executive power signified by "strength," "force" or "might." Accordingly we are commanded to direct our whole intention to God, and this is signified by the words "with thy whole heart"; to submit our intellect to God, and this is expressed in the words "with thy whole mind"; to regulate our appetite according to God, in the words "with thy whole soul"; and to obey God in our external actions, and this is to love God with our whole "strength," "force" or "might."
Chrysostom [*The quotation is from an anonymous author's unfinished work (Opus imperf. Hom. xlii, in Matth.) which is included in Chrysostom's works], on the other hand, takes "heart" and "soul" in the contrary sense; and Augustine (De Doctr. Christ. i, 22) refers "heart" to the thought, "soul" to the manner of life, and "mind" to the intellect. Again some explain "with thy whole heart" as denoting the intellect, "with thy whole soul" as signifying the will, "with thy mind" as pointing to the memory. And again, according to Gregory of Nyssa (De Hom. Opif. viii), "heart" signifies the vegetative soul, "soul" the sensitive, and "mind" the intellective soul, because our nourishment, sensation, and understanding ought all to be referred by us to God.
This suffices for the Replies to the Objections.
II–II · Q. 44, Art. 6: Whether it is possible in this life to fulfil this precept of the love of God?
Whether it is possible in this life to fulfil this precept of the love of God?
Objection 1: It would seem that in this life it is possible to fulfil this precept of the love of God. For according to Jerome [*Pelagius, Exposit. Cath. Fid.] "accursed is he who says that Cod has commanded anything impossible." But God gave this commandment, as is clear from Dt. 6:5. Therefore it is possible to fulfil this precept in this life.
Objection 2: Further, whoever does not fulfil a precept sins mortally, since according to Ambrose (De Parad. viii) sin is nothing else than "a transgression of the Divine Law, and disobedience of the heavenly commandments." If therefore this precept cannot be fulfilled by wayfarers, it follows that in this life no man can be without mortal sin, and this is against the saying of the Apostle (1 Cor. 1:8): "(Who also) will confirm you unto the end without crime," and (1 Tim. 3:10): "Let them minister, having no crime."
Objection 3: Further, precepts are given in order to direct man in the way of salvation, according to Ps. 18:9: "The commandment of the Lord is lightsome, enlightening the eyes." Now it is useless to direct anyone to what is impossible. Therefore it is not impossible to fulfill this precept in this life.
On the contrary, Augustine says (De Perfect. Justit. viii): "In the fulness of heavenly charity this precept will be fulfilled: Thou shalt love the Lord thy God," etc. For as long as any carnal concupiscence remains, that can be restrained by continence, man cannot love God with all his heart.
I answer that, A precept can be fulfilled in two ways; perfectly, and imperfectly. A precept is fulfilled perfectly, when the end intended by the author of the precept is reached; yet it is fulfilled, imperfectly however, when although the end intended by its author is not reached, nevertheless the order to that end is not departed from. Thus if the commander of an army order his soldiers to fight, his command will be perfectly obeyed by those who fight and conquer the foe, which is the commander's intention; yet it is fulfilled, albeit imperfectly, by those who fight without gaining the victory, provided they do nothing contrary to military discipline. Now God intends by this precept that man should be entirely united to Him, and this will be realized in heaven, when God will be "all in all," according to 1 Cor. 15:28. Hence this precept will be observed fully and perfectly in heaven; yet it is fulfilled, though imperfectly, on the way. Nevertheless on the way one man will fulfil it more perfectly than another, and so much the more, as he approaches by some kind of likeness to the perfection of heaven.
Reply to Objection 1: This argument proves that the precept can be fulfilled after a fashion on the way, but not perfectly.
Reply to Objection 2: Even as the soldier who fights legitimately without conquering is not blamed nor deserves to be punished for this, so too he that does not fulfil this precept on the way, but does nothing against the love of God, does not sin mortally.
Reply to Objection 3: As Augustine says (De Perfect. Justit. viii), "why should not this perfection be prescribed to man, although no man attains it in this life? For one cannot run straight unless one knows whither to run. And how would one know this if no precept pointed it out."