Adam Clarke's Commentary on the Bible

Verse 11 (Philippians 2:11)

And that every tongue should confess - That all those before mentioned should acknowledge that Jesus Christ is Lord, or absolute governor, and thus glorify God the Father, who has exalted this human nature to this state of ineffable glory, in virtue of its passion, death, resurrection, and the atonement which it has made, by which so many attributes of the Divine nature have become illustrated, the Divine law magnified and made honorable, and an eternal glory provided for man.

Others by things in heaven understand the holy angels; by things on earth, human beings generally; and by things under the earth, fallen spirits of every description. Perhaps the three expressions are designed to comprehend all beings of all kinds, all creatures; as it is usual with the Hebrews, and indeed with all ancient nations, to express, by things in heaven, things on earth, and things under the earth, all beings of all kinds; universal nature. See similar forms of speech, Exodus 20:4 ; Deuteronomy 4:17 , Deuteronomy 4:18 ; Psalm 96:11 ; and Ezekiel 38:20 . But intelligent beings seem to be those which are chiefly intended by the words of the apostle; for it appears that nothing less than absolute rule over angels, men, and devils, can be designed in these extraordinary words, and by confessing him to be Lord we may understand that worship which all intelligent creatures are called to pay to God manifested in the flesh; for all should honor the Son even as they honor the Father. And the worship thus offered is to the glory of God; so that far from being idolatrous, as some have rashly asserted, it is to the honor of the Divine Being. We may add, that the tongue which does not confess thus, is a tongue that dishonors the Almighty.

- Adam Clarke's Commentary on the Bible