Hadithcore
Mishkat al-Masabih, 3359

Rafi‘ b. Makith reported the Prophet (ﷺ) as saying, “Treating those under one’s authority well produces prosperity, but an evil nature produces evil fortune.” Abu Dawud transmitted it, but only in <i>al-Masabih</i> have I seen the additional words, “<i>Sadaqa</i> guards against an evil type of death and kindness lengthens life.”

وَعَنْ رَافِعِ بْنِ مَكِيثٍ أَنَّ النَّبِيَّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ قَالَ: «حُسْنُ الْمَلَكَةِ يُمْنٌ وَسُوءُ الْخُلُقِ شُؤْمٌ» . رَوَاهُ أَبُو دَاوُدَ وَلَمْ أَرَ فِي غَيْرِ الْمَصَابِيحِ مَا زَادَ عَلَيْهِ فيهِ منْ قولِهِ: «والصَّدَقةُ تمنَعُ مِيتةَ السُّوءِ والبِرُّ زيادةٌ فِي العُمُرِ»

References1 variant
In-Book Reference
Book 13, Hadith 272