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:1881 – ʿAbdullāh > ʿAlī > Sayyār > Jaʿfar > Mālik b. Dīnār

[Machine] I heard Malik ibn Dinar say, "The intention of the believer is more important than his action."  

الزهد لأحمد:١٨٨١ – حَدَّثَنَا عَبْدُ اللَّهِ حَدَّثَنَا عَلِيٌّ حَدَّثَنَا سَيَّارٌ حَدَّثَنَا جَعْفَرٌ قَالَ

سَمِعْتُ مَالِكَ بْنَ دِينَارٍ يَقُولُ «نِيَّةُ الْمُؤْمِنِ أَبْلَغُ مِنْ عَمَلِهِ»  

See similar narrations below:

Collected by Aḥmad's Zuhd, Suyūṭī
ahmad-zuhd:1603 – ʿAbdullāh from my father > Abū ʿUbaydah ʿAbd al-Muʾmin > al-Ḥasan

[Machine] I heard al-Hasan saying, "Intention is more significant than the act itself."  

الزهد لأحمد:١٦٠٣ – حَدَّثَنَا عَبْدُ اللَّهِ حَدَّثَنِي أَبِي حَدَّثَنَا أَبُو عُبَيْدَةَ عَبْدُ الْمُؤْمِنِ قَالَ

سَمِعْتُ الْحَسَنَ يَقُولُ «النِّيَّةُ أَبْلَغُ مِنَ الْعَمَلِ»