Albert Barnes Commentary Job 38:20

"That thou shouldest take it to the bound thereof, And that thou shouldest discern the paths to the house thereof?" — Job 38:20 (ASV)

That you should take it to the bounds of it - Margin, “or, at.” The sense seems to be this: God asks Job whether he was so well acquainted with the sources of light, and the place where it dwelled, that he could take it under his guidance and lead it back to its dwelling place.

And that you should know the paths to the house of it? - The same idea is repeated here. Light has a home, a dwelling place. It was far distant - in some region unknown to man. Did Job know the way in which it came, and the place where it dwelled so well, that he could lead it back to its own dwelling? Umbreit, Noyes, and Herder suppose that this is to be understood ironically.

“For you have reached its boundaries!
For then you know the path to its dwelling!”

But it has been commonly regarded as a question, and thus understood it accords better with the connection.