Do I have to make up the prayers I missed for four years during which I did not perform ghusl, or is repentance sufficient?

Praying without purification is among the major sins and is considered as if it never happened because it is invalid. It has been narrated that a man was flogged in his grave merely for praying without purification and for passing by an oppressed person without helping him. Scholars have differed regarding making up these prayers, but the most preponderant opinion is that they do not need to be made up, based on the saying of the Prophet Muhammad, peace be upon him: "Whoever performs an action which is not in accordance with our matter (religion), will have it rejected." What is obligatory upon one who has done this is: repentance, a firm resolve not to return to it, and to increase in supererogatory prayers, for Allah Almighty says: "Indeed, good deeds do away with evil deeds."