1)
Why did he say "va'Ani Batachti Alecha Hashem"?
1.
Radak: They thought to kill me. I trusted in You, for You are my G-d, i.e. Master and Judge over me, and they are not.
2.
Malbim: Even though I have no one to recognize and save me, I trusted in You, for You supervise over me and save me.
