Why does it say "Hatu Aznechem"?
Malbim: First tilt you ears to hear my words, and afterwards understand and accept them.
Why does it say "u'Schi Nafshechem"?
Malbim: Now, your Nefashos are wrapped in hunger and thirst to hear Divrei Elokim Chayim.
Will Yeshayah make a Bris?
Malbim: I will tell you Nevu'os about the Bris that Hashem will make with you forever, to guard for you Chasdei David ha'Ne'emanim.
What are "Chasdei David"?
Rashi: What I will bestow to David for his Chasadim.
Radak #1: This is Mashi'ach. His name will be David - "v'David Avdi Nasi Lahem l'Olam" (Yechezkel 37:25).
Radak #2, according to Kli Paz: He will teach the nations - "v'Shafat Bein ha'Goyim v'Hochi'ach l'Amim Rabim" (2:4).
Malbim: "Chasdei Hashem Olam Ashirah... Ad Olam Achin Zar'echa" (Tehilim 89:2, 5).
Why does it say "ha'Ne'emanim"
Radak: They are lasting. This is like "b'Makom Ne'eman" (22:23). Just like My Chesed with David endures, so My Bris with you endures.