'Judge between me and them with a [decisive] judgment' [Qur'an 26:118], meaning: decree a judgment between me and them. This was when he was commanded to invoke [curse] against them, so his prayer was answered, and Allah destroyed them.
Surat ash-Shu'ara' from (verse 123 to verse 140).
﴿فافتح بيني وَبينهمْ فتحا﴾ أَيْ: اقْضِ بَيْنِي وَبَيْنَهُمْ قَضَاءً؛ وَهَذَا حِينَ أُمِرَ بِالدُّعَاءِ عَلَيْهِمْ، فاستجيب لَهُ فأهلكهم الله.
سُورَة الشُّعَرَاء من (آيَة ١٢٣ آيَة ١٤٠).