John Calvin Commentary Genesis 1:9

"And God said, Let the waters under the heavens be gathered together unto one place, and let the dry land appear: and it was so." — Genesis 1:9 (ASV)

Let the waters... be gathered together This also is an illustrious miracle, that the waters by their departure have given a dwelling-place to humankind. For even philosophers concede that the natural position of the waters was to cover the whole earth, as Moses declares they did in the beginning; first, because being an element, it must be circular; and because this element is heavier than the air and lighter than the earth, it should cover the latter in its whole circumference. But that the seas, being gathered together as on heaps, should give place for humankind, is seemingly supernatural; and therefore Scripture often praises the goodness of God in this particular. See Psalm 33:7:

He has gathered the waters together on a heap,
and has laid them up in his treasures.

Also Psalm 78:13:

He has collected the waters as into a bottle.

Jeremiah 5:22:

Will you not fear me? Will you not tremble at my presence,
who have placed the sand as the boundary of the sea?

Job 38:8:

Who has shut up the sea with doors? Have not I surrounded it with gates and bars?
I have said,
Hitherto you shall proceed; here shall your swelling waves be broken.

Let us, therefore, know that we are dwelling on dry ground, because God, by His command, has removed the waters so that they should not overflow the whole earth.