1)
Why did he say "Ki Hayisa Ezrasah Li"?
1.
Radak: It is proper that I always remember You and sing to You, for You helped me. In all that they chased me, they did not catch me to harm me.
2)
Why did he say "uv'Tzel Kenafecha Aranen"?
1.
Radak: In the shade of Your wings I take refuge and sing.
2.
Malbim: I sing that I took refuge in the shade of Your wings.
