Commentaria in Isaiam
Hence, secondly, St. Gregory, Moralia, book 19, chapter 16, teaches from this passage of Isaias that Saints often pursue and perfect more fervently a good work which they began more tepidly. For, explaining that of Job 29: I shall multiply my days as a palm tree, he says: “The palm is broader at the top than it began at the root, because often the conversion of the elect accomplishes more in finishing than it proposed in beginning: and if it begins the first things more tepidly, it completes the last more fervently, since it always thinks itself to be beginning, and therefore perseveres untiring in newness.” He proves it by adding: “The Prophet, looking at this constancy of the just, says: They that trust in the Lord shall change their strength, etc. For they change strength, because they who were lately strong in the flesh strive to be strong in spiritual work. They take wings as eagles, because they preach with great swiftness to the swift. They walk and do not faint, because they retain the swiftness of their understanding, so as to condescend to the slower. And in all the good things they receive, the more willingly they share them with others, the more themselves they persevere unchangeable in newness, and they who set out slight from the root of their beginning grow strong in the perfection of the summit.”
So Moschus relates in the Spiritual Meadow, chapter 5, that a certain negligent Religious took on a great fervor toward the end, and when he was asked the cause of so great a change, said: “I am about to die. And after three days he died.” Think daily, when you rise: Today perhaps I shall die, and you will be fervent all day, and will not feel the labor.
Note: “They shall take wings as eagles” can be taken in two ways. First, for flying; for eagles, by renewing their feathers and taking new ones, fly with new swiftness, as if to say: The weary, by hoping in God, will take on new strength, so as to fly to good works with new alacrity, like eagles. Secondly, for running: for so the ostrich has wings not for flying but for running most swiftly. But the sense comes to the same; for flying is properly of eagles, but running of men, as if to say: Those who hope in God will be so swift in the way of virtue that, when they run down it, they will seem not so much to run as to fly; and will appear not so much men as eagles. Hence he explains “They shall take wings as eagles” when he adds: “They shall run and not labor,” as if to say: For those who hope in God are prepared the wings of eagles and a swiftness by which the immense spaces of works and virtues they may traverse with ever whole and vigorous flight, or run down at such swift pace that they seem not so much to walk on feet as to fly on wings. Hence the Chaldee translates: they shall run upon the wings of eagles.
Note secondly, “they shall walk and not faint” is nearly the same as what went before, “they shall run and not labor.” For in Hebrew it is yalak, that is, he went, he walked; for progress is ascribed also to Angels, lightning and winds, which do not so much walk as run: so it is ascribed to the Cherubim, Ezechiel 1:9, 12 and 13, who yet “went like the appearance of a flash of lightning,” in the same place, verse 14; for to go and to walk signifies to the Hebrews progress, whether it be made step by step in walking, or swiftly in running, or even in flying.
Therefore in this place these three, namely to fly, to run and to walk, signify almost the same thing; but to fly signifies impetus and ease, to run swiftness, to walk continuation and progress, namely the effect of flying and running, which is to advance one’s step and position toward the goal and end of the journey. For it is difficult to keep up a run, but easy to keep up a walk; hence, to signify that the Saints keep up this run, he adds that they walk, so that they do not faint, are not wearied; the Septuagint: do not hunger (for hunger follows from lack of strength), but any weariness they feel they overcome and surmount, their vigor and strength of mind restored. The same Saint, therefore, having received from God the wings of grace, flies, runs and walks the way of virtue constantly to the end of life, indeed even to heaven, and so in the way they shall walk, the sentence does not fall off, but rather grows and is perfected, as if to say: They shall walk continually until they reach the goal, namely heaven.
Note thirdly: These three can, however, be separated, and adapted to three degrees of those who hope; whence from the Hebrew with Pagninus you may translate thus: Those who hope in the Lord shall change strength, shall ascend on high like an eagle, shall run and not labor, shall walk and not be wearied. Vatablus: they shall lift up wings like an eagle, that is, they shall fly. The first degree, then, of those who hope in God is of those who, fervent with the love of God, transcending human things in mind, like eagles, indeed like Angels, fly to God in heaven, and say with the Apostle: “Our conversation is in heaven.” Such were the Apostles, of whom he says, Isaias 60:8: “Who are these, that fly as clouds?” Likewise those who lead the contemplative life, such as were the Essenes, and as now are not a few Religious. The second degree of those who hope in God is of those who are fervent in the active life, and by fervor run, who therefore on account of fervor do not feel the labor, as I said a little before. The third degree is of those who in the same life do not indeed run ardently, but yet walk constantly. You will say: So the sentence falls off, and one descends from the highest degree to the lowest, namely from flying to walking. I answer first: This has little or no inconvenience; for so we often descend from the more perfect to the less perfect. I answer secondly: Granted that on one side the sentence falls off here, yet on the other side it rises, and perhaps Isaias hints at a mystery lying hidden here, namely, as if to say: The highest Saints fly in contemplation, by raptures and ecstasies, to God; they are indeed the highest; but for these a grave danger of illusion hangs over, lest they be deceived by Satan transforming himself into an angel of light and fall, as has befallen many. The middle ones run, namely those who, moved by sensible devotion from God, are fervent for works of charity, mortification, missions; but for these there is danger from a spirit of singularity, pride and vanity, by which they secretly suppose themselves to be eminent above the rest and holier. Again, such persons, when sensible devotion fails, easily fall, and become listless and lukewarm. The lowest appear to be those who walk slowly indeed but constantly in the way of virtue; they are those who follow the same manner of living in their own degree, for example those who in Religion observe all the rules exactly and constantly, who bear the yoke of Religion constantly to death, and overcome labor, difficulties and temptations of every kind to the last breath of life. This degree, though it seems the lowest of excellence, is yet first in security, and often in fruit: for a run is often cut short, but a walk is always continued, so that the walker continually at length outstrips the runner, according to that of Proverbs 13:11: “Substance got in haste shall be diminished; but he that gathereth little by little with his hand shall increase.” Hence St. Bernard and the other Saints urge that he who is zealous for his salvation and progress should take up this degree of walking before the others; for by walking daily, that is, by advancing in virtue, how great an increase of virtues is made through single months and years? How great a heap of merits grows? And this perhaps Isaias wished to note, namely that those who hope in the Lord, if they would enter securely on the way of God, ought in it not so much to run and fly as to walk, that is, to go forward and advance constantly in the common manner of living of their state; for to walk is to make progress, says St. Bernard, sermon 49 on the Canticle; for so one goes surely to a holy death, and thence to blessed immortality; nor is there here the danger of illusion, or of singularity and pride, which is among those who fly and run.