Allah tells us that His servant and Messenger Dawud, peace be upon him, was endued with power

Al-Ayd means strength in knowledge and action. Ibn `Abbas, may Allah be pleased with him, As-Suddi and Ibn Zayd said, "Al-Ayd means strength." Mujahid said, "Al-Ayd means strength in obedience to Allah." Qatadah said, "Dawud, peace be upon him, was given strength in worship and the proper understanding of Islam." He told us that he, peace be upon him, used to spend a third of the night in prayer, and he fasted for half a lifetime. This was reported in the Two Sahihs, where it is recorded that the Messenger of Allah ﷺ said:

«أَحَبُّ الصَّلَاةِ إِلَى اللهِ تَعَالَى صَلَاةُ دَاوُدَ، وَأَحَبُّ الصِّيَامِ إِلَى اللهِ عَزَّ وَجَلَّ صِيَامُ دَاوُدَ، كَانَ يَنَامُ نِصْفَ اللَّيْلِ، وَيَقُومُ ثُلُثَهُ، وَيَنَامُ سُدُسَهُ، وَكَانَ يَصُومُ يَوْمًا وَيُفْطِرُ يَوْمًا، وَلَا يَفِرُّ إِذَا لَاقَى، وَأَنَّهُ كَانَ أَوَّابًا»

Commentary

It was said in verse 17 وَاذْكُرْ‌ عَبْدَنَا دَاوُودَ ذَا الْأَيْد (and remember Our servant, Dawud, the man of might). Nearly all commentators have explained it in the sense that he used to demonstrate great courage and strength during the course of his acts of worship (` ibadah), therefore, soon after it, comes the sentence: إِنَّهُ أَوَّابٌ (Surely, he was ever-turning to Allah - 38:17). Accordingly, in a Hadith of the Sahihayn (al-Bukhari and Muslim), the Holy Prophet ﷺ said: "In sight of Allah, the most liked Salah is the Salah of Dawud (علیہ السلام) and the most liked fasts are the fasts of Dawud (علیہ السلام) . He would sleep half a night, worship a third of it, and then sleep during the sixth part, and would fast one day and remain without fast on the other; and when he confronted the enemy, he would never desert the battlefield; and, without any doubt, he turned to Allah sincerely and profusely." (Tafsir Ibn Kathir)