What do we learn from "va'Yitzamdu l'Ba'al Pe'or"?
Sanhedrin 64a #1: Yisrael clung to Ba'al Pe'or like a Tzamid Pasil (a tightly sealed container). 1
Sanhedrin 64a #2: They were like a Tzamid (bracelet) on a woman's hand (that does not cling).
Malbim: They did not cling to Ba'al Pe'or intrinsically, amidst heresy. Rather, it was amidst lust for Zenus with Bnos Mo'av. Through this, they called them to the Korbanos of their gods, and via this they clung to Ba'al Pe'or. Since the primary reason was Zenus, when Pinchas killed Zimri, Hashem's anger departed from Yisrael. Our verse begins with the end - they clung to Ba'al Pe'or via eating from the Korbanos of their gods.
The Gemara expounds "ha'Nitzmadim l'Ba'al Pe'or" (Bamidbar 25:5), surely, the same applies to our verse. (PF)
What do we learn from "va'Yochelu Zivchei Mesim"?
Avodah Zarah 29b: Just like one may not benefit from a Mes, also from Korbanos to idolatry.
Avodah Zarah 32b: Just like a Mes has Tum'as Ohel, also what is offered to idolatry.
Avodah Zarah 50a: Just like a Mes is never Batel (it is always forbidden), also Takroves (something offered to idolatry) can never be Batel.
Radak: It says "va'Tikrenah la'Am l'Zivchei Eloheihem" (Bamidbar 25:2) - their gods are dead.
Malbim: Refer to 106:28:1:3.
