Caution: Translations of Quran and Ḥadīth may lead to possible misapplications and misinterpretations. This site is intended for students of sacred knowledge that are proficient in comprehending classical Arabic and have a strong foundation in Islamic sciences. Also note that religious injunctions rely on several aspects beyond what one may glean through reading individual aḥādīth.
Qurʾān Bukhārī Muslim Nasāʾī Abū Dāwūd Tirmidhī Ibn Mājah Mālik Aḥmad Dārimī Ḥākim Ibn Ḥibbān Ṭabarānī Nasāʾī's Kubrá Bayhaqī al-Luʾluʾ wa-al-Marjān Ibn Rajab's Fifty Riyāḍ al-Ṣāliḥīn Aḥmad's Zuhd Suyūṭī
quran:9:39 –

If you do not go forth, He will punish you with a painful punishment and will replace you with another people, and you will not harm Him at all. And Allah is over all things competent.  

If (illā: lā has been assimilated with the nūn of the conditional particle in, in both instances ˹here and in the next verse˺) you do not go forth, ˹if you do not˺ set out with the Prophet (s) for the struggle, He will chastise you with a painful chastisement, and He will substitute ˹you with˺ another folk other than you, that is, He will bring them in your place, and you will not hurt Him, that is, God, or ˹‘him’ as being˺ the Prophet (s), at all, should you neglect to help him ˹to victory˺, for God ˹Himself˺ will indeed bring victory to His religion; for God has power over all things, including bringing victory to His religion and His Prophet.
القرآن:٩:٣٩ –

إِلَّا تَنْفِرُوا يُعَذِّبْكُمْ عَذَابًا أَلِيمًا وَيَسْتَبْدِلْ قَوْمًا غَيْرَكُمْ وَلَا تَضُرُّوهُ شَيْئًا ۗ وَاللَّهُ عَلَىٰ كُلِّ شَيْءٍ قَدِيرٌ  

{إلاّ} بإدغام لا في نون إن الشرطية في الموضعين {تنفروا} تخرجوا مع النبي ﷺ للجهاد {يعذبكم عذابا أليما} مؤلماً {ويستبدل قوما غيركم} أي يأت بهم بدلكم {ولا تضروه} أي الله أو النبيَّ ﷺ {شيئا} بترك نصره فإن الله ناصر دينه {والله على كل شيء قدير} ومنه نصر دينه ونبيه.