Hosea 7:9

Strangers have devoured his strength, and he hath known it not. For by 'strangers' are usually understood apostate angels, who devour our strength, when they consume the virtue of the mind by perverting it. Which Ephraim both endured, and knew it not, because through the temptation of malignant spirits he both lost the strength of his mind, and understood not that he had lost it. Want therefore goes before the face of Leviathan, because he spoils by his temptation the minds of the careless, before he who is tempted knows his snares.

Not content with these words, the blessed Anthony entered upon a wider field of discussion, and he said, "This way of life and this most lukewarm condition not only causes you the loss that I have spoken of, even though you yourself may not feel it now. You may even somehow say in keeping with a sentence from Proverbs: 'They strike me, but I did not grieve, and they mocked me, but I was unaware.' And remember what is said by the prophet Hosea: 'Aliens devoured his strength, and he himself did not even recognize it.' "

"Foreigners have devoured his strength, and he knew it not. Yea, gray hairs also are spread upon him, and he is not aware of it." LXX: "strangers have devoured his strength, and he knew it not: yea, gray hairs are here and there upon him, yet he knoweth not." The Assyrians and the Chaldeans have eaten up its strength, and whatever it could have in terms of power, they have devoured. And the madness was such that he did not know that he had been devoured, or indeed did not know the reason for which he had been handed over to the devourers: in short, he remained in the mistaken belief until old age, that is, until the ultimate captivity. The demons have eaten his strength: for they are indeed strangers and enemies of all Christians, and he did not know, thinking adversaries were friends, and considering his devourers as guests; but they also poured out like dogs upon him, indeed they flourished, that is, he erred for a long time; and nevertheless he ignored his old age and antiquity, about which it is written, "What grows old and aged, is near extinction" (Heb. VIII, 13). And if it is said of the just man and the ecclesiastic: "The wisdom of his intellect is the dog of a man." (Wisdom 4:8): Why should it not be said of the wicked and the heretic: "The stupidity of his intellect is the dog of a man?" Concerning this old age Daniel spoke to the elder: "Thou hast grown old in days of wickedness" (Dan. III, 52). Wherefore also in the book of the Pastor (if, however, one is pleased to receive it), the Church seems to be first seen as an old man, then as a youth, and finally as a maiden adorned with hair.