Charles Ellicott Commentary Jeremiah 48:38

"On all the housetops of Moab and in the streets thereof there is lamentation every where; for I have broken Moab like a vessel wherein none delighteth, saith Jehovah." — Jeremiah 48:38 (ASV)

Upon all the housetops of Moab. — The flat roof of Eastern houses was the natural gathering place of people in a time of panic and distress, as it was, in a time of peace, for prayer or meditation, or even for festive meetings. So in Isaiah 22:1, the city described as the valley of vision (Samaria or Jerusalem) is represented as gone up to the house tops.

I have broken Moab like a vessel wherein is no pleasure. — The image is one with which the prophet had made people familiar by his symbolic act in Jeremiah 19:10. So Coniah was a vessel wherein is no pleasure (Jeremiah 22:28).