FROM BibleHub dot com:
Ellicott's Commentary for English Readers-
(11) As I live.—The original has, “I have sworn by Myself,” for which St. Paul, quoting from memory, substitutes another common Hebrew formula—“As I live,” or, “by my life.”
Shall confess . . .—The Greek word is capable of two renderings—“confess” and “praise:” Most commentators prefer the latter, but it is not quite clear that the English version is wrong. That the word can bear this meaning is, especially in view of James 5:16, unquestionable, and the sense seems to agree better with the next verse.

Matthew Henry's Concise Commentary
14:7-13 Though some are weak, and others are strong, yet all must agree not to live to themselves. No one who has given up his name to Christ, is allowedly a self-seeker; that is against true Christianity. The business of our lives is not to please ourselves, but to please God. That is true Christianity, which makes Christ all in all. Though Christians are of different strength, capacities, and practices in lesser things, yet they are all the Lord's; all are looking and serving, and approving themselves to Christ. He is Lord of those that are living, to rule them; of those that are dead, to revive them, and raise them up. Christians should not judge or despise one another, because both the one and the other must shortly give an account. A believing regard to the judgment of the great day, would silence rash judgings. Let every man search his own heart and life; he that is strict in judging and humbling himself, will not be apt to judge and despise his brother. We must take heed of saying or doing things which may cause others to stumble or to fall. The one signifies a lesser, the other a greater degree of offence; that which may be an occasion of grief or of guilt to our brother.

Barnes' Notes on the Bible:
For it is written - This passage is recorded in Isaiah 45:23. It is not quoted literally, but the sense is preserved. In Isaiah there can be no doubt that it refers to Yahweh. The speaker expressly calls himself Yahweh, the name which is appropriate to God alone, and which is never applied to a creature; Romans 14:18. In the place before us, the words are applied by Paul expressly to Christ; compare Romans 14:10. This mode of quotation is a strong incidental proof that the apostle regarded the Lord Jesus as divine. On no other principle could he have made these quotations.

As I live - The Hebrew is, "I have sworn by myself." One expression is equivalent to the other. An "oath" of God is often expressed by the phrase "as I live;"
COMPARE: “Numbers 14:21; Isaiah 49:18; Ezekiel 5:11; Ezekiel 14:16.”
Saith the Lord - These words are not in the Hebrew text, but are added by the apostle to show that the passage quoted was spoken by the Lord, the Messiah;
COMPARE: Isaiah 45:18, Isaiah 45:22.

Every knee shall bow to me - To bow the knee" is an act expressing homage, submission, or adoration. It means that every person shall acknowledge him as God, and admit his right to universal dominion. The passage in Isaiah refers particularly to the homage which "his own people" should render to him; or rather, it means that all who are saved shall acknowledge "him" as their God and Saviour. The original reference was not to "all men," but only to those who should be saved; Isaiah 45:17, Isaiah 45:21-22, Isaiah 45:24. In this sense the apostle uses it; not as denoting that "all men" should confess to God, but that all "Christians," whether Jewish or Gentile converts, should alike give account to Him.

"They" should all bow before their common God, and acknowledge "his" dominion over them. The passage originally did not refer particularly to the day of judgment, but expressed the truth that all believers should acknowledge his dominion. It is as applicable, however, to the judgment, as to any other act of homage which his people will render.
Every tongue shall confess to God - In the Hebrew, "Every tongue shall swear." Not swear "by God," but "to him;" that is, pay to him our vows, or "answer to him on oath" for our conduct; and this is the same as confessing to him, or acknowledging him as our Judge.