"Our Lord, make us not a trial" - meaning a tribulation - "for those who have disbelieved" - the verse. That is: do not let the polytheists overcome us, for then they would say: 'If these people were following the true religion, we would not have overcome them,' and thus they would be tempted/tested by us.
Tafsir of Surat al-Mumtahanah from verse 6 to verse 9.
﴿رَبنَا لَا تجعلنا فتْنَة﴾ بلية ﴿للَّذين كفرُوا﴾ الْآيَة؛ أَي: لَا تظهر علينا الْمُشْركين، فيقولوا: لَو كَانَ هَؤُلَاءِ على دين مَا ظهرنا عَلَيْهِم، فيفتنوا بِنَا.
تَفْسِير سُورَة الممتحنة من الْآيَة ٦ إِلَى آيَة ٩.
