1)
Who says "Shuvi Nafshi"?
1.
Radak: When I was afflicted, I said so to myself.
2)
What is "Menuchoychi"?
1.
Radak: [Return to] Hashem, for He will be rest for you.
3)
Why does it say "Ki Hashem Gamal Alaichi"?
1.
Malbim: Do not worry - Hashem crushed you with afflictions due to Gemul - based on deeds, or due to His love and Hashgachah Pratis.
