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
bukhari:2443 – ʿUthmān b. Abū Shaybah > Hushaym > ʿUbaydullāh b. Abū Bakr b. Anas And Ḥumayd al-Ṭawīl Samiʿā Anas b. Mālik

Messenger of Allah ﷺ said, "Help your brother, whether he is an oppressor or he is an oppressed one."  

البخاري:٢٤٤٣ – حَدَّثَنَا عُثْمَانُ بْنُ أَبِي شَيْبَةَ حَدَّثَنَا هُشَيْمٌ أَخْبَرَنَا عُبَيْدُ اللَّهِ بْنُ أَبِي بَكْرِ بْنِ أَنَسٍ وَحُمَيْدٌ الطَّوِيلُ سَمِعَا أَنَسَ بْنَ مَالِكٍ ؓ يَقُولُ

قَالَ رَسُولُ اللَّهِ ﷺ انْصُرْ أَخَاكَ ظَالِمًا أَوْ مَظْلُومًا  

See similar narrations below:

Collected by Suyūṭī