1)
What is the meaning of "Uzo Elecha Eshmorah"?
1.
Rashi: The strength of my enemy (Radak - Sha'ul), who is strong against me, I wait for You to help me against him.
2.
Malbim: You (Hashem) say to me in jest 'know that I will guard the strength of Sha'ul to you.' I will guard his strength and kingship to you; you will rule in place of him, and you will be strong against the nations in war.
2)
Why did he say "Ki Elokim Misgabi"?
1.
Radak: I have no refuge other than You.
2.
Malbim: So You say to me, via being my refuge and strengthening me against Sha'ul and against Pelishtim in the war of Ke'ilah. Via this, You inform that Sha'ul's strength is guarded for me, and I am prepared to reign in place of him.
