Full Sharh — Mishkat al-Masabih 3299
وَعَنْ كَعْبِ بْنِ مَالِكٍ قَالَ: قُلْتُ: يَا رَسُولَ اللَّهِ إِنَّ مِنْ تَوْبَتِي أَنْ أَنْخَلِعَ مِنْ مَالِي صَدَقَةً إِلَى اللَّهِ وَإِلَى رَسُولِهِ فَقَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ: «أَمْسِكْ بَعْضَ مَالِكَ فَهُوَ خَيْرٌ لَكَ» . قُلْتُ: فَإِنِّي أُمْسِكُ سَهْمِي الَّذِي بِخَيْبَر. وَهَذَا طرف من حَدِيث مطول
English Translation
Ka'b b. Malik told that he said, “Messenger of God, to make my repentance complete* I should divest myself of my property as sadaqa for God and His Messenger.” God's Messenger replied, “Retain some of your property, for that will be better for you.” So he said he would retain the portion he had at Khaibar. (Bukhari and Muslim.) This is part of a long tradition. * Mirqat, iii, 566 refers this to his withdrawal from the expedition to Tabuk without a valid reason. Pt. 10
Source
Mishkat al-Masabih(مشكاة المصابيح)
Oaths and Vows
Hadith Number
3299