He said to the Messenger of Allah ﷺ when his repentance was accepted, "Messenger of Allah, I will divest myself of my wealth as charity to Allah and His Messenger."The Messenger of Allah ﷺ said to him, "Keep some of your wealth for yourself, that is better for you."Abu Abdul-Rahman said, It seems likely that Zuhri heard this hadith from Abdullah bin Kaab and also from Abdul-Rahman who narrated it from him, within this lengthy hadith concerning the repentance of Kaab.
حدثنا يونس بن عبد الأعلى قال حدثنا ابن وهب قال أخبرني يونس عن ابن شهاب قال أخبرني
أنه قال لرسول الله ﷺ حين تيب عليه يا رسول الله إني أنخلع من مالي صدقة إلى الله ورسوله فقال له رسول الله ﷺ أمسك عليك بعض مالك فهو خير لك قال أبو عبد الرحمن يشبه أن يكون الزهري سمع هذا الحديث من عبد الله بن كعب ومن عبد الرحمن عنه في هذا الحديث الطويل توبة كعب
[Its isnad is sahih] Abu Dawud narrated it in Kitab al-Ayman wal-Nudhur, Bab man nadhara an yatasaddaqa bimalihi, hadith no. 3318, from the hadith of Ibn Wahb, in an abridged form. It is also found in Al-Kubra, hadith no. 4765, and it is agreed upon (by Bukhari and Muslim) as a lengthy hadith. Bayhaqi and others graded it sahih.