‏الوصية : Hadeeth No:4005 Abu Huraira (Allaah be pleased with him) reported Allaah's Messenger (sallAllaahu alayhi wa sallam) as saying: When a man dies, his acts come to an end, but three, recurring charity, or knowledge (by which people) benefit, or a pious son, who prays for him (for the deceased)....

‏الفضائل : Hadeeth No:5687 Umm Salama reported that she heard Allaah's Prophet (sallAllaahu alayhi wa sallam) saying this as he was sitting on the pulpit and she was getting her hair combed. (He uttered these words):" O people." And she said to one who was combing: Leave my head; the rest of the hadith is the same....