What is "b'Nefesh Tzarai"?
Rashi: In the desire of my haters, that their desire about me be fulfilled. Radak - this is like "Im Yesh Es Nafshechem" (Bereishis 23:8). They want that I will not have time for Avodas Hashem, rather, all my days I will engage in wars, in bodily toil.
What is the meaning of "Edei Sheker vi'Fei'ach Chamas"?
Rashi #1: It is people who speak Sheker. Radak - they testify and say that I am a Rasha, a murderer, and I have no share in Hashem - "Elokim Azavo", "Davar Beliya'al Yatzuk Bo" (71:11, 41:9).
Rashi #2: [Vi'Fei'ach] is an expression of a pitfall.
Malbim: They testified falsely about me to Sha'ul, in order that he kill me.
Malbim (based on Brachos 4a): They are foreign mindsets that arose in my heart when I saw a Tzadik perish in his virtue. This arouses claims against Hashgachah, like it explains in Sefer Iyov. David's afflictions testified [against Hashgachah]! His Emunah nullified the claims. In place of Tzadikim's afflictions in this world, they will receive double in the world to come. If not for my Emunah in the world to come, I would have denied Hashgachah and reward and punishment.
