Hosea 5:3

“I know Ephraim, and Israel is not hid from me, etc.] Though they may cover their designs from men, and seek deep to hide their counsel from the Lord, and make plausible pretences for what they do, and put on an appearance of religion; yet God, who knows all men, and their hearts, cannot be deceived; he judges not according to outward appearance; all things are naked and open to him; nor can any hide themselves from him; he knows their persons, intentions, and designs, as well as actions. Kimchi interprets Ephraim of Jeroboam, the son of Nebat, who was of that tribe; others, of the tribe itself, and Israel of the other nine tribes; others take Ephraim for the ten tribes, and Israel for the…”

“Ephraim--the tribe so called, as distinguished from "Israel" here, the other nine tribes. It was always foremost of the tribes of the northern kingdom. For four hundred years in early history, it, with Manasseh and Benjamin, its two dependent tribes, held the pre-eminence in the whole nation. Ephraim is here addressed as foremost in idolatry. I how . . . not hid from me--notwithstanding their supposed profound cunning (Hos 5:2; Rev 2:2, Rev 2:9, Rev 2:13, Rev 2:19). now--"though I have been a rebuker of all them" (Hos 5:2) who commit such spiritual whoredoms, thou art now continuing in them.”

“I know Ephraim - There is much emphasis on the “I.” It is like our, “I have known,” or “I, I, have known.” God had known him all along, if we may so speak. However deep they may have laid their plans of blood, however they would or do hide them from man, and think that no eye seeth them, and say, “Who seeth me? and who knoweth me? I, to whose eyes all things are naked and opened Hebrews 4:13, have all along known them, and nothing of them has been hid from Me. For, He adds, even now, now when, under a fair outward show, they are veiling the depth of their sin, now, when they think that their way is hid in darkness, I know their doings, that they are defiling themselves. Sin never wanted…”

“5:3 you are utterly defiled: The word translated defiled is used frequently in the Pentateuch to describe ritual uncleanness, a physical condition that disqualified a person from worshiping God in the Temple (Lev 11–15). The prophets used the concept as a metaphor for Israel’s moral uncleanness as the result of her idolatry (Isa 6:5; Mic 2:10).”

“know: Amo 3:2; Heb 4:13; Rev 3:15 Ephraim: Hos 5:9, Hos 5:11, Hos 5:13, Hos 6:4, Hos 8:11, Hos 12:1, Hos 13:1; Gen 48:19, Gen 48:20; Deu 33:17; Isa 7:5, Isa 7:8, Isa 7:9, Isa 7:17 thou: Hos 4:17, Hos 4:18; Kg1 12:26-33, Kg1 14:14-16; Ezek. 23:5-21 Hosea 5:4”

“"I know Ephraim, and Israel is not hid from me: for now, O Ephraim, thou hast committed whoredom; Israel has defiled itself. Hos 5:4. Their works do not allow to return to their God, for the spirit of whoredom is in them, and they know not Jehovah." By עתּה, the whoredom of Ephraim is designated as in fact lying before them, and therefore undeniable; but not, as Hitzig supposes, an act which has taken place once for all, viz., the choice of a king, by which the severance of the kingdoms and the previous idolatry had been sanctioned afresh. נטמא, defiled by whoredom, i.e., idolatry. Their works do not allow them to return to their God, because the works are merely an emanation of the…”