Adam Clarke on Psalms 8:6

Thou madest him to have dominion - Jesus Christ, who, being in the form of God, and equal with God, for a time emptied himself, and made himself of no reputation; was afterwards highly exalted, and had a name above every name. See the notes referred to above, and those on Phi 2:6-9 (note).

Thou hast put all things under his feet - Though the whole of the brute creation was made subject to Adam in his state of innocence; yet it could never be literally said of him, that God had put all things under his feet, or that he had dominion over the work of God's hands; but all this is most literally true of our Lord Jesus; and to him the apostle, Heb 2:6, etc., applies all these passages.