Did Hashem finish His anger?
Rav Sadya Gaon: No, He eradicated b'Chamaso (amidst His anger).
Rashi: Yes. It was burning in Him for many years. He finished it via taking vengeance.
Ri Kara: Yes, He poured all of it on them, like "Chitzai Achaleh Bam" (Devarim 32:23), like "v'Chilisi Chamasi Bam" (Yechezkel 6:12).
Refer to 4:11:2:3.
What is the significance of the fire in Tziyon?
Bava Kama 60b: Hashem said 'I lit the fire in Tziyon; I must pay for it. I will rebuild it with fire - "I will be like a wall of fire around (Yerushalayim)."'
Ibn Ezra #1: This was His anger.
Ibn Ezra #2: Hunger in the body is like fire. It reaches the foundations in the bones.
Palgei Mayim: After Hashem poured all His anger via the many afflictions, He needed also to pour His anger and burn the Mikdash. If not, He would have eradicated Klal Yisrael!