Why did he say "Netatam"?
Radak: Planting is a metaphor for their success, which endures and increases. Their good comes from Hashem; it is not chance - "u'Meshalem l'Son'av El Panav Leha'avido" (Devarim 7:10).
Malbim: Do not say that their children will be cut off, like Iyov's friend Bildad held.
What is the grammatical form of "Shorasho"?
Radak: It is Kaved, of a four-letter root (even though it is written without a Vov). The same applies to "Bal Shoresh ba'Aretz Giz'am" (Yeshayah 40:24).
What is the meaning of "Karov Atah b'Fihem"?
Radak: If they pray to You or mention You in a Shevu'ah, it is for Sheker, for You are far from their kidneys, and they do not think that their benefit is in Your hand, and that You benefit and harm.
Radak citing Targum Yonasan: Words of Your Torah are close (frequent) in their mouths.
Malbim: The Rasha believes in punishments of Hashem and the roots of Emunah. He sins due to his desire. There is hope that he will repent afterwards for his deeds. However, since you are far from their kidneys, they do not believe in You at all. There is no hope that they will repent.
