Surah Al-Anfal 8:66

ٱلْـَٔـٰنَ خَفَّفَ ٱللَّهُ عَنكُمْ وَعَلِمَ أَنَّ فِيكُمْ ضَعْفًا ۚ فَإِن يَكُن مِّنكُم مِّا۟ئَةٌ صَابِرَةٌ يَغْلِبُوا۟ مِا۟ئَتَيْنِ ۚ وَإِن يَكُن مِّنكُمْ أَلْفٌ يَغْلِبُوٓا۟ أَلْفَيْنِ بِإِذْنِ ٱللَّهِ ۗ وَٱللَّهُ مَعَ ٱلصَّـٰبِرِينَ

Now, Allāh has lightened [the hardship] for you, and He knows that among you is weakness. So if there are from you one hundred [who are] steadfast, they will overcome two hundred. And if there are among you a thousand, they will overcome two thousand by permission of Allāh. And Allāh is with the steadfast.

Translation: Saheeh International

Tafsir

Now God has lightened the burden for you for He knows that there is weakness read du‘fan or da‘fan in you making you unable to fight ten times your number. So if there be read as yakun or takun a hundred of you steadfast they will overcome two hundred of them; …

Excerpt from Tafsir al-Jalalayn, commentary on 8:66, via Quran.com. The reader has the full commentary and 9 more tafsirs.