"Our Lord has encompassed everything in knowledge"—meaning, our Lord has filled everything with knowledge.
"Our Lord, judge between us and our people"—meaning, deliver a judgment.
Qatada said: When the Prophet would supplicate to his Lord to judge between him and his people, the punishment would come to them.
﴿وسع رَبنَا﴾ أَيْ: مَلَأَ رَبُّنَا ﴿كُلَّ شيءٍ علما﴾.
﴿رَبَّنَا افْتَحْ بَيْنَنَا وَبَيْنَ قَوْمِنَا﴾ أَيْ: احْكُمْ.
قَالَ قَتَادَةُ:
وَإِذَا دَعَا النَّبِيُّ رَبَّهُ أَنْ يَحْكُمَ بَيْنَهُ وَبَيْنَ قَوْمِهِ، جَاءَهُمُ الْعَذَابُ.
