Shaykh Saalih al-Fowzaan said:
I heard Shaykh Muhammad ibn Ibraaheem [Aal ash-Shaykh] rahima-hullaah at a talk he delivered at some of the special events [which took place] at the Faculty of Sharee’ah [at Imaam Muhammad University in Riyadh]. He brought this hadeeth* [up for discussion] and [he] said that the ongoing charity may [well] cease, and the righteous child will die – meaning that their benefits will come to an end. However, beneficial knowledge continues and does not cease; its benefit continues, and [likewise] the reward for the one who conveyed it. And this is what distinguishes [beneficial] knowledge from other righteous deeds.
* Abu Hurayrah reported the Messenger of Allaah (sal-Allaahu ’alayhi wa sallam) said:
«When a person dies, his deeds end except for three: ongoing charity, beneficial knowledge, or a righteous child who prays for him.» – Saheeh Muslim, no.1631