Is it obligatory to make up for the fasting of the past four years, from puberty until the beginning of fasting, and is it permissible to make it up only by fasting on Mondays and Thursdays, or must it be made up quickly?

Fasting is a great act of worship and one of the pillars of Islam. The questioner must repent and seek forgiveness for having neglected fasting in previous years. She must make up for the fasting of those years, and it is recommended for her to hasten in making up for them immediately and continuously. She is permitted to fast on Mondays and Thursdays to make up for Ramadan. If she delayed the make-up fasting until the next Ramadan due to ignorance or forgetfulness, she is not required to pay expiation (fidyah). However, if she delayed it intentionally without a valid excuse, then she must pay expiation by feeding one poor person for each day (750 grams of the staple food of the country). The obligation to make up for missed fasts is the view of the majority of scholars, and it is the most preponderant and the one given in fatwas.