Is a senior woman who receives a monthly pension after the death of her husband required to pay zakat on this pension, and how is it calculated? Is she obligated to pay zakat for past months for which she did not pay it, and if so, how can she secure the money for that without hardship? Will she be sinful if she fails to pay zakat in the future?

The ruling on retirement salary regarding ownership differs based on the retirement system. Zakat becomes obligatory when its conditions are met, and retirement salary is subject to zakat like any other salary, specifically on what is saved from it. If all the money is spent or a nisab (minimum threshold) is not maintained, then there is no zakat on it until it reaches the nisab and a hawl (one lunar year) passes over it, after which each saved portion is to be zakated. A person is not obligated to set aside money specifically for paying zakat. As for previous years, if zakat became obligatory and was not paid, it must be paid immediately and does not lapse with the passage of time. Whoever is unable to pay it due to lack of money or needing it for life's necessities is not sinful, but must hasten to pay it as soon as they are able.