זָרְע֤וּ חִטִּים֙ וְקֹצִ֣ים קָצָ֔רוּ נֶחְל֖וּ לֹ֣א יוֹעִ֑לוּ וּבֹ֙שׁוּ֙ מִתְּבוּאֹ֣תֵיכֶ֔ם מֵחֲר֖וֹן אַף־יְהוָֽה׃ (ס)
They have sown wheat, and have reaped thorns; they have put themselves to pain, they profit not; be ye then ashamed of your increase, because of the fierce anger of the LORD. .
Rashi on Jeremiah
They sowed wheat, but they reaped thorns They prayed, but their prayer was not accepted. Why? Because they did not plow for themselves a furrow of repentance and good deeds. Therefore, they sowed seeds resulting in thorns. A book in which זרעו is vowelized with a ‘chirik’ under the ‘zayin,’ is erroneous.
Rashi on Jeremiah
they have become ill Heb. נחלו, an expression of illness. They have become ill with their pain and their cry before Me, but they did not avail.