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
tabarani:17256 – Muṭṭalib b. Shuʿayb al-Azdī > ʿAbdullāh b. Ṣāliḥ > Ḥarmalah b. ʿImrān > Abū al-Simṭ Saʿīd b. Abū Saʿīd al-Mahrī from his father > ʿAbdullāh b. ʿAmr b. al-ʿĀṣ > Muʿādh b. Jabal Arād Safar

that Muʿādh b. Jabal planned to go on a journey, so he said, "O Messenger of Allah ﷺ, ˹please˺ give me some advice." He said, "Worship Allah and do not associate anything with Him." Muʿādh said, "O Messenger of Allah, ˹please give me more advice.˺" He said, "When you have done something bad, then ˹follow it up with˺ doing good." Muʿādh said, "O Messenger of Allah, ˹please give me more advice.˺." The Prophet said, "Be steadfast ˹in these˺ and improve your character." (Using translation from Ḥākim 7616)  

الطبراني:١٧٢٥٦ – حَدَّثَنَا مُطَّلِبُ بْنُ شُعَيْبٍ الْأَزْدِيُّ ثنا عَبْدُ اللهِ بْنُ صَالِحٍ حَدَّثَنِي حَرْمَلَةُ بْنُ عِمْرَانَ أَنَّ أَبَا السِّمْطِ سَعِيدَ بْنَ أَبِي سَعِيدٍ الْمَهْرِيَّ حَدَّثَهُ عَنْ أَبِيهِ عَنْ عَبْدِ اللهِ بْنِ عَمْرِو بْنِ الْعَاصِ

أَنَّ مُعَاذَ بْنَ جَبَلٍ أَرَادَ سَفَرًا فَقَالَ يَا رَسُولَ اللهِ أَوْصِنِي قَالَ «اعْبُدِ اللهَ وَلَا تُشْرِكْ بِهِ شَيْئًا» قَالَ يَا رَسُولَ اللهِ زِدْنِي قَالَ «وَإِذَا أَسَأْتَ فَأَحْسِنْ» قَالَ يَا رَسُولَ اللهِ زِدْنِي قَالَ «اسْتَقِمْ وَلْتُحَسِّنْ خُلُقَكَ»  

See similar narrations below:

Collected by Ḥākim, Ibn Ḥibbān

Councils to Muʿādh b. Jabal before his journey to Yemen

hakim:7616 – Muḥammad b. Ṣāliḥ b. Hāniʾ > Ḥarmalah b. ʿImarān al-Tujībī > Abū al-Sumayṭ Saʿīd b. Abū Saʿīd al-Mahrī from his father > ʿAbdullāh b. ʿAmr > Muʿādh b. Jabal Arād Safar

that Muʿādh b. Jabal planned to go on a journey, so he said, "O Messenger of Allah ﷺ, ˹please˺ give me some advice." He said, "Worship Allah and do not associate anything with Him." Muʿādh said, "O Messenger of Allah, ˹please give me more advice.˺" He said, "When you have done something bad, then ˹follow it up with˺ doing good." Muʿādh said, "O Messenger of Allah, ˹please give me more advice.˺." The Prophet said, "Be steadfast ˹in these˺ and improve your character."  

This Ḥadīth has an sound chain but they did not collect.
الحاكم:٧٦١٦ – حَدَّثَنِي مُحَمَّدُ بْنُ صَالِحِ بْنِ هَانِئٍ ثَنَا حَرْمَلَةُ بْنُ عِمَرَانَ التُّجِيبِيُّ أَنَّ أَبَا السُّمَيطِ سَعِيدَ بْنَ أَبِي سَعِيدٍ الْمَهْرِيَّ حَدَّثَهُ عَنْ أَبِيهِ عَنْ عَبْدِ اللَّهِ بْنِ عَمْرٍو

أَنَّ مُعَاذَ بْنَ جَبَلٍ أَرَادَ سَفَرًا فَقَالَ: يَا رَسُولَ اللَّهِ، أَوْصِنِي۔ قَالَ: «اعْبُدِ اللَّهَ وَلَا تُشْرِكْ بِهِ شَيْئًا» قَالَ: يَا رَسُولَ اللَّهِ، زِدْنِي۔ قَالَ: «إِذَا أَسَأْتَ فَأَحْسِنْ» قَالَ: يَا رَسُولَ اللَّهِ، زِدْنِي۔ قَالَ: «اسْتَقِمْ وَلْتُحَسِّنْ خُلُقَكَ»  

هَذَا حَدِيثٌ صَحِيحُ الْإِسْنَادِ وَلَمْ يُخَرِّجَاهُ صحيح
hakim:179 – Ismāʿīl b. Muḥammad b. al-Faḍl al-Shaʿrānī from my father > ʿAbdullāh b. Ṣāliḥ > Ḥarmalah b. ʿImrān al-Tujībī > Abū al-Simṭ Saʿīd b. Abū Saʿīd al-Mahrī from his father > ʿAbdullāh b. ʿUmar > Muʿādh b. Jabal Arād Safar

[Machine] "O Messenger of Allah, advise me." He said, "Worship Allah and associate nothing with Him." He said, "O Messenger of Allah, tell me more." He said, "If you do evil, then do good." He said, "O Messenger of Allah, tell me more." He said, "Be upright and strive to improve your character."  

الحاكم:١٧٩ – حَدَّثَنَاهُ إِسْمَاعِيلُ بْنُ مُحَمَّدِ بْنِ الْفَضْلِ الشَّعْرَانِيُّ ثنا جَدِّي ثنا عَبْدُ اللَّهِ بْنُ صَالِحٍ حَدَّثَنِي حَرْمَلَةُ بْنُ عِمْرَانَ التُّجِيبِيُّ أَنَّ أَبَا السِّمْطِ سَعِيدَ بْنَ أَبِي سَعِيدٍ الْمَهْرِيَّ حَدَّثَهُ عَنْ أَبِيهِ عَنْ عَبْدِ اللَّهِ بْنِ عُمَرَ أَنَّ مُعَاذَ بْنَ جَبَلٍ أَرَادَ سَفَرًا فَقَالَ

يَا رَسُولَ اللَّهِ أَوْصِنِي قَالَ «اعْبُدِ اللَّهَ وَلَا تُشْرِكْ بِهِ شَيْئًا» قَالَ يَا رَسُولَ اللَّهِ زِدْنِي قَالَ «إِذَا أَسَأْتَ فَأَحْسِنْ» قَالَ يَا رَسُولَ اللَّهِ زِدْنِي قَالَ «اسْتَقِمْ وَلْتُحَسِّنْ خُلُقَكَ»  

«هَذَا حَدِيثٌ حَسَنٌ صَحِيحُ الْإِسْنَادِ مِنْ رِوَايَةِ الْبَصْرِيِّينَ وَلَمْ يُخَرِّجَاهُ» صحيح الإسناد

ذِكْرُ الْإِخْبَارِ بِأَنَّ عَلَى الْمَرْءِ تَعْقِيبَ الْإِسَاءَةِ بِالْإحْسَانِ مَا قَدَرَ عَلَيْهِ فِي أَسْبَابِهِ

ibnhibban:524 – Muḥammad b. al-Ḥasan b. Qutaybah > Yazīd b. Mawhab > Ibn Wahb > Ḥarmalah b. ʿImrān al-Tujībī > Saʿīd b. Abū Saʿīd al-Maqburī from his father > ʿAbdullāh b. ʿAmr b. al-ʿĀṣ

that Muʿādh b. Jabal planned to go on a journey, so he said: O Prophet of Allah, ˹please˺ give me some advice. He said, "Worship Allah and do not associate anything with Him." He said: O Prophet of Allah, ˹please give me more advice.˺ He said, "When you have done something bad, then ˹follow it up with˺ doing good." He said: O Messenger of Allah, ˹please give me more advice.˺. He said, "Be steadfast ˹in these˺ and improve your character."  

ابن حبّان:٥٢٤ – أَخْبَرَنَا مُحَمَّدُ بْنُ الْحَسَنِ بْنِ قُتَيْبَةَ قَالَ حَدَّثَنَا يَزِيدُ بْنُ مَوْهَبٍ قَالَ حَدَّثَنَا ابْنُ وَهْبٍ عَنْ حَرْمَلَةَ بْنِ عِمْرَانَ التُّجِيبِيِّ أَنَّ سَعِيدَ بْنَ أَبِي سَعِيدٍ الْمَقْبُرِيَّ حَدَّثَهُ عَنْ أَبِيهِ عَنْ عَبْدِ اللَّهِ بْنِ عَمْرِو بْنِ الْعَاصِ

أَنَّ مُعَاذَ بْنَ جَبَلٍ أَرَادَ سَفَرًا فقَالَ: يَا نَبِيَّ اللَّهِ أَوْصِنِي، قَالَ: «اعْبُدِ اللَّهَ، لَا تُشْرِكْ بِهِ شَيْئًا» قَالَ: يَا نَبِيَّ اللَّهِ زِدْنِي، قَالَ: «إِذَا أَسَأْتَ فَأَحْسِنْ» قَالَ يَا رَسُولَ اللَّهِ زِدْنِي قَالَ «اسْتَقِمْ وَلْيَحْسُنْ خُلُقُكَ۔»