Osama Bin Laden left a personal fortune of around $29m (£21m) after his death in a raid in 2011, his will shows.
He urged his family to “obey my will” and to spend his inheritance on “jihad, for the sake of Allah”.
In another letter, he urged his father to take care of his wife and children in the event of his death.
That message made it clear that the risk of being killed was present in his mind.
“If I am to be killed, pray for me a lot and give continuous charities in my name, as I will be in great need for support to reach the permanent home,” he wrote.
Although Bin Laden referred to the money as being in Sudan, it is not clear whether it was in the form of cash or assets, or whether any of it made its way to his heirs.
He lived in Sudan for five years in the 1990s as a guest of the Sudanese government.
In other letters, he gave his assessment of the progress of the West’s “war on terror” and the US military campaign in Afghanistan.
“They thought that the war would be easy and that they would accomplish their objectives in a few days or a few weeks,” he wrote.
“We need to be patient a bit longer. With patience, there is victory!”
Bin Laden was killed by US special forces in May 2011 in a raid on his compound in Abbotabad, Pakistan.
The group has since been led by al-Qaeda’s former second-in-command, Ayman al-Zawahiri.