Allah the Almighty says:
“Lo! We it is Who bring the dead to life. We record that which they send before (them, and their footprints. And all things We have kept in a clear Register.” (36:12)
On the authority of Abu Hurayrah, may Allah be pleased with him, who said:
The Messenger of Allah, peace and blessings of Allah be upon him, said:
When a human being dies,
their deeds are cut off, except for three:
except for ongoing charity,
or knowledge from which benefit is derived,
or a righteous child who prays for them.
Ibn al-Jawzi, may Allah have mercy on him, said:
If a person realizes that death will sever them from their deeds,
then let them perform in their lifetime that which will ensure their reward continues after their death.
If they possess worldly wealth,
let them establish an endowment or plant a crop,
and let them strive to raise offspring who will remember Allah after them, so that they may receive the reward.
Or, let them author a book on knowledge,
for the works of a scholar are like their immortal child,
and that is the one who does not truly die.