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
Ibn ‘Abbas reported God’s Messenger as saying, “If anyone takes a vow but does not name it, its atonement is the same as that for an oath; if anyone takes a vow to do an act of disobedience, its atonement is the same as that for an oath; if anyone takes a vow he is unable to fulfil, its atonement is the same as that for an oath; but if anyone takes a vow he is able to fulfil, he must do so.”
Abu Dawud and Ibn Majah transmitted it, but some traced it no farther back than Ibn ‘Abbas.
Ibn ‘Abbas told that Sa'd b. ‘Ubada asked the Prophet for a decision about a vow taken by his mother who had died before fulfilling it, and that he gave decision that he should fulfil it on her behalf.
