1)
Why did he say "Hakshivah"?
1.
Radak: They say that they will not heed me - You should heed me, i.e. my Tefilah!
2.
Malbim: He summonses Hashem to be a judge to hear his claims and their claims, and he will see who is correct in the quarrel.
2)
What is "Kol Yerivai"?
1.
Radak: The words that they speak about me.
