Why did he say "Amor Amarti"?
Rashi #1: I apportioned grandeur to Bnei Itamar twice. It says about Bnei Gershon and Bnei Merari "b'Yad Itamar" (Bamidbar 4:28, 33). Eli was from Itamar (Midrash Shmuel 8:3).
Rashi #2: Initially I gave Kehunah Gedolah to Elazar - "v'Hilbashtam Es Elazar" (Bamidbar 20:26). In the days of Pilegesh b'Giv'ah, Yisrael uprooted most Mitzvos. This was due to Pinchas and others like him; they should have gone around from city to city to rebuke people. I took Kehunah Gedolah from him and gave it to you; you are from Itamar. I said that [Radak - you and your father's house] will go in front of Me forever; when greatness is given to a person, it is for him and his children, forever (Megilah 13b).
Malbim: Until now, I intended [that you and your house will be Tzadikim and your grandeur will last forever]..
To whom does "Mechabdai Achaved" apply?
Rashi: It is Bnei Pinchas; he honored Me at Shitim (Bamidbar 25:1-9). In the days of Shlomo, when the Beis ha'Mikdash was built, "Shlomo expelled Evyasar from being Kohen, to fulfill what He said about Beis Eli", and appointed Tzadok Kohen Gadol in place of him (Melachim 1 2:27, 35); Tzadok was from Pinchas (Divrei ha'Yamim 1 5:29-34).
Why does it say "Yekalu", and not "Akel", similar to "Achaved"?
Rashi: I (Radak - My countenance) will leave them, and automatically they are belittled. 1
Radak citing Midrash Shmuel 8:3: Hashem was more stringent about a Tzadik's (Avraham's) honor than His own. "Mekalelecha A'or" (Bereishis 12:13 - Hashem himself will curse), and for His own honor, [Bnei Eli], Yekalu via others.
Whose honor is Hashem removing, and how was it removed?
Radak: It is only Eli's seed, but not other Kohanim, even though He said above "Beis Avicha", i.e. Aharon. They lost Kevod Kehunah 1 , i.e. Kehunah Gedolah; no descendant of Eli was Kohen Gadol, only secondary to him ("Sefacheni Na" - verse 36).
Radak: They lost also Bris Kehunah, i.e. Brisi Shalom given to Pinchas (Bamidbar 25:12). "Brisi Haysah Ito ha'Chayim veha'Shalom" (Mal'achi 2:5). Eli's seed "Yamusu Anashim" (verse 33, i.e. young), the opposite of the Bris, for they profaned the Bris and the honor of the Kehunah (Seder Olam Rabah 14).
