How is Hashem Seser for David?
Rashi: David can hide in His shade, from fear of the enemy.
Malbim: The flood guarded David from his enemies. They came to besiege his land, but could not, due to the flood.
What is the meaning of "Titzereni"?
Rashi: You will guard me.
Radak: You save me from afflictions that are punishment of my sin; You did not abandon me in the hand of my enemies.
What is "Rani Falet"?
Rashi: It is joyous singing due to salvation.
Why does it say "Tesoveveni"?
Rashi: Future tense used in place of present; You constantly surround me with singing of salvation.
Radak: Screams of salvation will surround me, corresponding to the enemies that surrounded me.
Malbim: It is as if You surrounded me with a camp singing about the salvation from the enemy.