What is the ruling concerning the prayers and fasting of a woman who, for many years, used to perform ghusl after menstruation after five days, without waiting for the signs of purity?

What the woman did was a grave error, as she used to perform ghusl before ensuring ritual purity and would neglect it afterwards. This renders her prayers invalid due to the lack of the purity condition. She is required to make up all her prayers, according to the majority of scholars. However, Sheikh al-Islam Ibn Taymiyyah held the view that she is not required to make them up due to her ignorance. She is permitted to follow Sheikh al-Islam's opinion if making up the prayers is difficult for her. If she makes up what is due, that is better.