Charles Ellicott Commentary Isaiah 45:23

"By myself have I sworn, the word is gone forth from my mouth [in] righteousness, and shall not return, that unto me every knee shall bow, every tongue shall swear." — Isaiah 45:23 (ASV)

I have sworn by myself. — The highest conceivable form of solemn declaration (Genesis 22:16; Jeremiah 22:5; Hebrews 6:13).

Unto me every knee shall bow. — The faith of Israel becomes the religion of mankind, though, from the prophet’s standpoint, Israel does not lose its distinctive nationality. We note the application of the words to the Christ in Philippians 2:10; Romans 14:11.