Is the beneficial knowledge mentioned in the Hadith: "When a person dies, all his deeds come to an end except for three:...", restricted to religious knowledge, or does it include beneficial worldly sciences such as physics, astronomy, and mathematics? And would establishing free lectures in these fields be considered beneficial knowledge for which one's reward continues after death?

Shaykh Ibn Uthaymeen explained that the Hadith (definition) "When the son of Adam dies, his deeds cease except for three: an ongoing charity, knowledge from which benefit is derived, or a righteous child who prays for him" includes all beneficial knowledge, whether religious or worldly, but religious knowledge is superior. And teaching a permissible craft from which people benefit falls within this reward. Moreover, establishing a website to facilitate knowledge and assist students is a beneficial and good deed, and it is considered one of the communal obligations (furood al-kifayat) for which the Ummah is rewarded. The reward is multiplied with a sincere intention for Allah the Almighty, in accordance with His saying: "So whoever does an atom's weight of good will see it," and the Prophet's (peace be upon him) saying: "Allah helps the servant as long as the servant helps his brother."