Lamentations 2:6 (ESV)

6 He has laid waste his booth like a garden, laid in ruins his meeting place; the LORD has made Zion forget festival and Sabbath, and in his fierce indignation has spurned king and priest.

For Jeremiah, the worst thing remains that the LORD has destroyed his own temple. From the days at Horeb, it has always been Israel’s greatest privilege that God wanted to dwell with them (Exodus 25:8; 1 Kings 6:13). Now he has taken away that gracious privilege. He has laid waste his own dwelling, the temple.

In doing that, the Lord also took away the feasts and the Sabbaths from his people. The weekly Sabbath was there to remind Israel of her covenant with God. It was the sign and seal of that covenant. The cycle of feasts (see Leviticus 23:1–44 were there to remind Israel of their salvation out of Egypt, God’s care for them, and his forgiveness of their sins. Now the feasts—and the things they symbolized—seem to be gone forever.

Lastly, in his fierce anger the Lord has also rejected his kings and priests. The kings and priests had for too long committed idolatry (2 Kings 6:10–16; 2 Kings 21:1–15). The fact that the Lord had rejected his priests means that the people of Judah had lost their right to approach him. After all, the priests were necessary as the “go-betweens” between the holy God and his people.