With whom was the Bris?
Rashi: It was with Pinchas.
Radak: It was with Aharon Kedosh Hashem, the head of the Shevet, and Pinchas, "Asher Kinei lEi'lokav" (Bamidbar 25:13).
How was the Bris "Chayim v'Shalom"?
Rashi: It was said to Pinchas "Es Brisi Shalom" (Bamidbar 25:12). It was promised to him and his seed after him - this shows that his seed will last forever. Radak - he was given life - we find that he lived more than 300 years, even according to the opinion that he is not Eliyahu. We find that he was in Pilegesh b'Giv'ah 1 - "u'Finchas ben Elazar ben Aharon Omed Lefanav ba'Yamim ha'Hem" (Shoftim 20:28).
Malbim: From My side, via the Bris I promised to him Chayim and Shalom - "Hineni Nosen Lo Es Brisi Shalom", "v'Shamru Mishmarti... v'Lo Yamusu Gam Hem Gam Atem" "v'Es Kodshei Bnei Yisrael Lo Sechalelu v'Lo Samusu" (Bamidbar 25:12, 18:3, 32).
According to the opinion that Pilegesh b'Giv'ah is written in its proper place, at the end of Sefer Shoftim, it was over 400 years after Yetzi'as Egypt. (PF)
What is the meaning of "va'Etenem Lo Mora"?
Rashi: I gave [Chayim and Shalom] to [Pinchas] to receive them with fear, and so he did - "va'Yira'eni".
Radak: I gave Chayim and Shalom to him due to his fear.
Radak citing Targum Yonasan: I taught to him My entire Torah.
Malbim: The Bris from his side was that I will give to him Mora, "va'Yira'eni" - he will have fear (awe) of My grandeur.
What do we learn from "Mipnei Shmi Nichas Hu"?
Brachos 12a: One should be submissive, i.e. bowed, before saying Hashem's name.
Rashi: Nichas is like "Chasas" (Iyov 6:21) - we will fear.
Radak: The root is Chasas; he is broken and submissive due to My name.
Malbim: He will also fear My punishment.
