Abu Habibah said: I asked Sayyiduna Abu Darda’ (may Allah be pleased with him): What is the ruling regarding a man who has dedicated his wealth in the way of Allah? Sayyiduna Abu Darda’ (may Allah be pleased with him) said: The Messenger of Allah (peace and blessings be upon him) said: “The one who gives charity or frees a slave at the time of his death is like the man who gives a gift after he is full.”
Hadith Referenceسنن دارمي / من كتاب الوصايا / 3258
In an authentic and agreed-upon hadith, it is stated: A man asked the Messenger of Allah (sallallahu alayhi wa sallam): Which charity is the greatest in terms of reward? The Prophet (sallallahu alayhi wa sallam) replied: Your giving charity while you are healthy and strong, desiring wealth, fearing poverty, and hoping for affluence, and you do not delay in giving charity until the soul reaches the throat, and then you say: For so-and-so this much, for so-and-so this much, while in fact it has already become the right of so-and-so (the heir). [بخاري : 1419] and [مسلم : 1032].
It is understood from this that the best charity is that which a person gives while in a state of health; giving charity after the signs of death have appeared is just as mentioned above: like giving away leftover food after one’s hunger has been satisfied.
Also, at the time of death, a person cannot give more than one-third of his wealth in charity, because at that time the wealth becomes the right of the heirs, which cannot be spent in the way of Allah. Therefore, Allah the Exalted has set a limit that if a person gives charity at the time of death, it should not exceed one-third. For this reason, a person should not delay in giving charity.