Isaiah 45:23

“I have sworn by myself, &c.] Christ being the true God, he could swear by no greater, (<580613>Hebrews 6:13), this shows that what follows, and is here sworn unto, is of great importance, and strictly true, and would certainly be accomplished: the word is gone out of my mouth in righteousness; both what goes before, that such that look unto him shall be saved; and also what follows, concerning the subjection of every creature to him; this was what he had resolved in his mind, and declared in his word, by promise and prophecy, should be; and as it was agreeably to truth and justice, it should certainly, and in faithfulness, be performed, and shall not return void and without effect, but be…”

“sworn by myself--equivalent to, "As I live," as Rom 14:11 quotes it. So Num 14:21. God could swear by no greater, therefore He swears by Himself (Heb 6:13, Heb 6:16). word . . . in righteousness--rather, "the truth (see on Isa 45:19) is gone forth from My mouth, the word (of promise), and it shall not return (that is, which shall not be revoked)" [LOWTH]. But the accents favor English Version. tongue . . . swear--namely, an oath of allegiance to God as their true King (see on Isa 19:18; Isa 65:16). Yet to be fulfilled (Zac 14:9).”

“I have sworn by myself - This verse contains a fuller statement of the truth intimated in the previous verse, that the benefits of salvation should yet be extended to all the world. It is the expression of God’s solemn purpose that all nations should yet be brought to acknowledge him, and partake of the benefits of the true religion. The expression, ‘I have sworn by myself,’ denotes a purpose formed in the most solemn manner, and ratified in the most sacred form. God could swear by no greater Hebrews 6:13, Hebrews 6:16; and this, therefore, is the most solemn assurance that could be possibly given that the purpose which he had formed should be executed. To swear by himself is the same as to…”

“In righteousness - It is what I will faithfully perform. Return - Without effect. It is a metaphor from ambassadors, who sometimes return to their princes without any success in their business. Every tongue - Not only the Jews, but all nations. Isaiah 45:24”

“45:23 God’s words are always true. God’s swearing by his own name reinforces the certainty that he will never go back on his word (see also 14:24; 54:9; 62:8; Heb 6:13). • Every knee . . . every tongue: At the end of time all nations will submit to his authority, whether willingly or unwillingly (see Rom 14:11; 1 Cor 15:25-27; Phil 2:10-11).”

“sworn: Gen 22:15-18; Jer 22:5, Jer 49:13; Amo 6:8; Heb 6:13-18 the word: Isa 45:19, Isa 55:11; Num 23:19 That unto: Rom 11:4, Rom 14:10-12; Phi 2:10 every tongue: Isa 19:18-21, Isa 44:3-5, Isa 65:16; Gen 31:53; Deu 6:13; Ch2 15:14, Ch2 15:15; Neh 10:29; Psa 63:11, Psa 132:2 Isaiah 45:24”