1)
What is "Shakadti"?
1.
Radak: I will strive and be zealous.
2)
Why does the verse equate building and planting to uprooting and destroying?
1.
Malbim: Uprooting is for the sake of planting, and destroying is for the sake of building. Both are attributed to Me. I am zealous to uproot and destroy, so I can be zealous to build and plant, just like one who seeds is zealous that the seed rot in the ground, in order that it will sprout.
