What is the meaning of "Yaguru Yitzponu"?
Rashi: They ambush and lodge in places where they hope that I will go, and they guard my footsteps, to tell about me and send my pursuers there. This was David's complaint about evil Yisraelim who ambushed him; from fear of them, he fled to Achish. "Yaguru" is lodging; "Yitzponu" is ambushing. Radak - this is like "Nitzpenah l'Naki Chinam" (Mishlei 1:11). They ambush in a hidden place.
Radak: "Yaguru" is gathering, like "Yaguru Alai Azim" (59:4).
Malbim: "Yaguru" is fear; they feared that he feigns insanity, therefore Yitzponu - they hid themselves when he left the Pelishtim, to see in which way he will go.
Why is it written Yatzpinu, and we pronounce it Yitzponu?
Radak: The Kesiv teaches that they themselves ambush, and take others to ambush me with them.
Why does it say "Akevai Yishmoru"?
Malbim: They check my steps, whether or not I go like a lunatic.
What is the meaning of "Ka'asher Kivu Nafshi"?
Rashi: When they know and hope that I will go on this path.
Radak: They hoped to trap me.
Malbim: They hoped to kill me.