וְיָצָ֥א מֵהֶ֛ם תּוֹדָ֖ה וְק֣וֹל מְשַׂחֲקִ֑ים וְהִרְבִּתִים֙ וְלֹ֣א יִמְעָ֔טוּ וְהִכְבַּדְתִּ֖ים וְלֹ֥א יִצְעָֽרוּ׃
And out of them shall proceed thanksgiving And the voice of them that make merry; And I will multiply them, and they shall not be diminished, I will also increase them, and they shall not dwindle away.
Read halakhic rulings (Jewish law) on Jeremiah 30:19: and classical halakhic sources.