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
ahmad-zuhd:317 – ʿAbdullāh > Bī > Hushaym > Mughīrah > al-Shaʿbī

[Machine] Jesus, the son of Mary, ﷺ , used to say, "Indeed, kindness is not that you show kindness to those who are kind to you. Rather, kindness is that you show kindness to those who have treated you poorly."  

الزهد لأحمد:٣١٧ – حَدَّثَنَا عَبْدُ اللَّهِ حَدَّثَنَا أبِي أَخْبَرَنَا هُشَيْمٌ أَنْبَأَنَا مُغِيرَةُ عَنِ الشَّعْبِيِّ قَالَ

كَانَ عِيسَى ابْنُ مَرْيَمَ عَلَيْهِ السَّلَامُ يَقُولُ إِنَّ الْإِحْسَانَ لَيْسَ أَنْ تُحْسِنَ إِلَى مَنْ أَحْسَنَ إِلَيْكَ إِنَّمَا تِلْكَ مُكَافَأَةٌ بِالْمَعْرُوفِ وَلَكِنَّ الْإِحْسَانَ أَنْ تُحْسِنَ إِلَى مَنْ أَسَاءَ إِلَيْكَ  

See similar narrations below:

Collected by Aḥmad's Zuhd
ahmad-zuhd:471 – ʿAbdullāh > Muḥammad b. Ḥassān al-Azraq > Ibn Mahdī > Abū 77 ʿAwānah > Mughīrah > al-Shaʿbī > ʿĪsá Ibn Maryam ʿAlayh al-Salām Lays al-Iḥsān

[Machine] To do good to those who have done good to you is a form of gratitude, but to do good to those who have wronged you is an act of excellence.  

الزهد لأحمد:٤٧١ – حَدَّثَنَا عَبْدُ اللَّهِ حَدَّثَنِي مُحَمَّدُ بْنُ حَسَّانَ الْأَزْرَقُ أَخْبَرَنَا ابْنُ مَهْدِيٍّ حَدَّثَنَا أَبُو [77] عَوَانَةَ عَنْ مُغِيرَةَ عَنِ الشَّعْبِيِّ قَالَ قَالَ عِيسَى ابْنُ مَرْيَمَ عَلَيْهِ السَّلَامُ لَيْسَ الْإِحْسَانُ

أَنْ تُحْسِنَ إِلَى مَنْ أَحْسَنَ إِلَيْكَ تِلْكَ مُكَافَأَةٌ بِالْمَعْرُوفِ وَلَكِنَّ الْإِحْسَانَ أَنْ تُحْسِنَ إِلَى مَنْ أَسَاءَ إِلَيْكَ