All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger.
We have already issued Fataawa 85067 and 113207 clarifying that if a sick person is permanently unable to fast, he should feed a poor person for each day that he missed.
However, it is not a condition that he feeds (the poor) from his own earnings; rather if a person was given money or charity, then this money becomes his own money by possessing it, and once he possesses it, it is permissible for him to dispose of it as he wishes, including paying the expiation as the Prophet had given a Miktal (a large basket which equals approximately 15 Saa’ = 22.5 kgs) of dates to a man who had sexual intercourse with his wife during the day of Ramadan, and he told him: “…take this and donate it in charity…” [Al-Bukhari and Muslim]
In addition to this, Al-Bukhari entitled a chapter in his book as “The chapter of whoever helps a person in difficulty in paying expiation” and he mentioned the Hadeeth that we have referred to above.
To conclude, it is not a condition that the expiation be from one’s earnings; so it is permissible for you to pay the expiation from the money the government pays you. For more benefit, please refer to Fatwa 116310.
Allaah Knows best.