עַל־זֹ֛את חִגְר֥וּ שַׂקִּ֖ים סִפְד֣וּ וְהֵילִ֑ילוּ כִּ֥י לֹא־שָׁ֛ב חֲר֥וֹן אַף־יְהֹוָ֖ה מִמֶּֽנּוּ׃ (פ)
For this gird you with sackcloth, lament and wail; For the fierce anger of the LORD Is not turned back from us.
Read halakhic rulings (Jewish law) on Jeremiah 4:8: and classical halakhic sources.