How did water aggrandize it and the depth elevate it?
Rashi citing Pesikta Rabasi 33: Because Anshei Ninveh heeded Yonah, who descended to the depth, and they repented from the theft in their hands [they were elevated].
Radak: It had abundant water, therefore it was elevated so much, i.e. it had great success. Tehom is a depth of great water that never ceases ? so its grandeur did not cease for many days, until its time [to fall] came. The Tehom is a metaphor for good and great success.
Malbim: The cedar had much water on top ? via this it grew. It had a pond of water below ? via this it was elevated more.
Which rivers are discussed, and where do they go?
Radak, Malbim: They are rivers of the Tehom, i.e. each river that comes out of the Tehom goes around this cedar that was planted on the Tehom.
What are "Te'aloseha"?
Rashi: They are irrigation channels.
Radak: They are small streams, like "Te'alas ha'Berechah" (Yeshayah 7:3).
What is the significance of sending its channels to all trees?
Rashi: It waters them.
Rashi citing Targum Yonasan: It subjugated many nations under its rule. Its authority was over all lands.
Radak: Melech Ashur had great good and success; other kings had little.
Malbim: The Tehom sends rivers around the cedar, but mere streams to the other trees. The Nimshal is, rainwater and the Tehom are the wealth of Ashur ? seas surround it. It received the primary influence; the other nations received a small influence via the streams.