Surah Ash-Shu'ara, ayah 3

26:3

لَعَلَّكَ بَٰخِعٞ نَّفۡسَكَ أَلَّا يَكُونُواْ مُؤۡمِنِينَ ٣

La'allaka bākhi'un nafsaka allā yakūnū mu'minīn

Perhaps, [O Muḥammad], you would kill yourself with grief that they will not be believers.