Tafsir of Al-Jathiyah 45:12

Allah is the One Who subjected for you the sea by making its surface smooth so that things may float upon it, permeable like wood, while not preventing one from diving into it, so that ships may sail upon it by His command—meaning by His subjecting it and facilitating its use. It is also said: by His creation or by His permission, Majestic and Exalted is He. The context of bestowing favor dictates that the meaning is "so that ships may sail upon it while you are its passengers," and that you may seek of His bounty through trade, diving, fishing, and other means, and that you may give thanks—that is, so that you may be grateful for the blessings resulting from that.

This—meaning "Allah is the One Who subjected," and so on—was mentioned to complete the rebuke. For this reason, He connected to it the immediate purposes, as it is something that generally necessitates gratitude, even from the disbeliever. It is as if it were said: "Those signs are more worthy of gratitude." For this reason, He followed it with that which encompasses both categories [of people], namely His saying, Glorified is He: