Ibn Jarīr At Tabarī mentions a narration from Mujāhid regarding this verse.

Mujāhid says:

“Amongst The Banū Isrāīl there was a man who would stand at night [to pray] until morning. Then he would fight the enemy (جihād) until evening. He did this for 1000 months. Allāh then

revealed this verse. Standing [to pray] in this night is better than the actions of that man (from Banū Isrāīl).”

Ibn Kathīr also narrates a similar narration from Ibn Abī Hātim.

‏وَقَالَ ابْنُ جَرِيرٍ: حَدَّثَنَا ابْنُ حُمَيْدٍ، حَدَّثَنَا حَكَّام بْنُ سَلْمٍ، عَنِ الْمُثَنَّى بْنِ الصَّبَاحِ، عَنْ مُجَاهِدٍ قَالَ: كَانَ فِي بَنِي إِسْرَائِيلَ رَجُلٌ يَقُومُ اللَّيْلَ حَتَّى يُصْبِحَ ثُمَّ يُجَاهِدُ الْعَدُوَّ بِالنَّهَارِ حَتَّى يُمْسِيَ ‏فَفَعَلَ ذَلِكَ أَلْفَ شَهْرٍ، فَأَنْزَلَ اللَّهُ هَذِهِ الْآيَةَ: ﴿لَيْلَةُ الْقَدْرِ خَيْرٌ مِنْ أَلْفِ شَهْرٍ﴾ قِيَامُ تِلْكَ اللَّيْلَةِ خَيْرٌ مِنْ عَمَلِ ذَلِكَ الرَّجُلِ