Preparing one’s will
Preparing the will is an act of Sunnah during health and illness.
The Prophet (PBUH) says:
“It is the duty of a Muslim who has something which is to be given as a bequest, not to let two nights pass without having his will written down with him.”
(Al-Bukhāriy no. 2783, Muslim no. 1626)
By “two nights” the Prophet (PBUH) means to symbolize for a short period of time, not specifically two nights. This has been stressed on because no one knows exactly when they will die. As for the rights of Allāh Almighty regarding Zakat, Hajj, or any sort of Kaffārah (i.e. expiation), in addition to people’s rights regarding debts, they are obligatory and not just Sunnah, so one must write them down in his will, especially if no one knows about them, and there is a rule in Principles of Fiqh that states, “Whatever thing an obligation cannot be accomplished without, is an obligation.”