Jerusalem is the city of the Great King, Jesus Christ (Psalm 48:2; Matthew 5:35). Its splendor is promised to God forever (Psalm 87:3; cf. 132:13). Further, it is the Zion of the OT (Psalm 132:13-18).
However, greater than Mt. Zion is God’s own righteousness. And, as the Jews continue to reject God, especially in light of the Son of God, Jesus Christ, the Messiah of the OT, having come in the flesh as promised, God will continue to reject them. He will reject them until it is time to restore them, which He will do as a demonstration of His great power over sin and the human heart.
But, historically, God has punished Jerusalem in significant ways. Some of the most atrocious expressions of God’s wrath on sin and rebellion were during the sieges of Babylon and Rome. Babylon assaulted Jerusalem three times: 605 B.C., 597 B.C., and finally took the city in 586 B.C. During that affliction, Jeremiah wrote in his long book of the siege (esp. Jeremiah 52) and dedicated an entire book to that very event, the book of Lamentations.
In Leviticus 26:29 and, written years later, Deuteronomy 28:53-59 is a promise to punish Jerusalem, and Israel, for her rebellion and disobedience. What was the punishment? In these specific verses, the punishment would be cannibalism. That is, mothers and fathers would be famished and being deranged would boil their own infants and eat them because of the lack of food.
What kind of a God would do this? What kind of a God would allow for, and prophesy, such a grotesque and horrific act? What kind of God would make such a big deal of disobedience that He would permit the cannibalism of children? What kind of God? I will tell you: a holy God.
The seriousness of sins manifests in the punishment that comes upon the sinner. For example, a serial murderer would surely get a worse punishment for his crimes than a petty thief. In God’s estimation, Israel’s crimes were reprehensible and against His great glory to such a degree and for such a long time-frame, that the expression of their own waywardness would be allowed to manifest itself.
It is not different than Romans 1 in which God said that He gave the nations over to indulge in the desire of the flesh. What was the result? Homosexuality. The worst of all perversions of the natural, created, order. He further is letting rampant unrighteousness, wickedness, greed, evil, etc… run full. Why? Because this is in OUR HEARTS!
The siege of Jerusalem and the resultant cannibalism, which was also recorded historically in Jeremiah 2:20; 4:10, and illustrated in Samaria in 2 Kings 6:26-29, is not simply God making these men and women commit a grotesque act. It is God withholding His restraint and allowing them to do what they wished. He warned them. He left them to themselves.