Charles Ellicott Commentary Lamentations 2:15

"All that pass by clap their hands at thee; They hiss and wag their head at the daughter of Jerusalem, [saying], Is this the city that men called The perfection of beauty, The joy of the whole earth?" — Lamentations 2:15 (ASV)

All that pass by. — The triumphant exultation of the enemies of Zion came to add bitterness to her sorrows. They reminded her of what she had been in the past, and contrasted it with her present desolation.

The perfection of beauty ... — Like phrases are used of Zion in Psalms 48:2 and Psalms 50:2; and of Tyre in Ezekiel 27:3. Now that beauty was turned into squalor and desolation.