John Gill Commentary Proverbs 8:29

"When he gave to the sea its bound, That the waters should not transgress his commandment, When he marked out the foundations of the earth;" — Proverbs 8:29 (ASV)

When he gave to the sea his decree, that the waters should
not pass his commandment
A perpetual decree, which never has been altered nor never will: he has placed the sand for the bounds of the sea everywhere, which it cannot pass, though its waves toss, foam, and roar; this is his decreed place, with which he has shut it up, as with doors, bars, and bolts; so that those proud waves may come hitherto and no further, (Jeremiah 5:22) (Job 38:10Job 38:11) ;

when he appointed the foundations of the earth ;
which are laid on the seas and floods; nay, the earth is hung like a ball in the air upon nothing; and yet its foundations are such as that it shall not be removed; being the purpose and decree, the power and might, of the Lord himself, (Job 26:7) (Psalms 24:2) (104:5) .

Now Christ was present when those were laid, for he was concerned in the laying of them himself, (Hebrews 1:10) . The Lord asks Job where he was then, (Job 38:4) ; he was not then in being, but Christ was.