What do we learn from "Ki Lo l'Olam Ariv v'Lo la'Netzach Ektzof"?
Eruvin 54a: Whenever it says 'Netzach 1 ', the matter will never cease.
Rashi: I f I bring afflictions on a person, my strife will not be for long, and My anger will not be forever.
Radak: From when they were a nation to Me until now, I quarreled with them. They sin, and I am angry at them. This will not be forever. I will remove the stone heart from them, and I will make that they will go in My Chukim.
Malbim: Sometimes Hashem punishes a person and quarrels with him - Ariv. Sometimes He does not punish, only He is angry and hides His face and guards anger - Ektzof
54a: We learn from verses that the same applies to 'Selah' and 'va'Ed'.
What do we learn from "Ki Ru'ach mi'Lefanai Ya'atof"?
Nidah 13b: [Mashi'ach] Ben David will not come until all Neshamos in 'Guf' (a treasury) are completed 1 .
Rashi: When man's Ru'ach, which is in front of Me - it was given to him from Me - it will faint, admit and be humbled for its transgression. This is like "ha'Atufim b'Ra'av", "b'Atef Olel (Eichah 2:19, 11). "Ki" here means when, like "Ki Sir'eh", "Ki Savo." When his spirit is faint, and he is humbled, I nullify My quarrel and anger from him.
Radak: The Ru'ach is in front of Me. It will wrap and clothe the body, and conquer it to go in the good path.
Targum Yonasan: In the future, I will return the Ru'ach of the dead. Radak - he explains that the verse discusses Techiyas ha'Mesim.
Malbim: Hashem cannot punish forever, due to His Chesed with the body. The life Ru'ach comes in front of Him - how could He crush it forever?!
Tosfos (13b DH Ad): Chazal said that Mashi'ach could have come earlier, e.g. had Yisrael guarded two Shabbosos in the Midbar (Shabbos 118b). Women would have given birth to many at once, in order that all the Neshamos be born first.
Why does it say "u'Neshamos Ani Asisi"?
Radak: It is as if it says mi'Lefanai. The Neshamah does not have the land's nature, like the body does. The body sins and follows animalistic desire, and draws the Ru'ach after it. It will not be so forever. Man will recognize that the Neshamos are in front of Me, and I alone made them; they do not have the land's nature. "Ki Mal'ah ha'Aretz De'ah Es Hashem" (Yeshayah 11:9). This will be from the day that I raise them from Galus, and revive them from the death of Galus.
Malbim: Hashem's hidden anger cannot be forever, due to His Chesed with the Neshamah, which is a 'part' of Hashem. He made it - how could He guard the sin forever?!