What should I do about the past years during which I did not pray or fast, given that God has now guided me and I have become remorseful?

The majority of jurists hold that one who abandons prayer does not become an unbeliever, and therefore, he must make up the missed prayers and fasts. However, some jurists have ruled that abandoning prayer constitutes disbelief, based on evidence such as the saying of the Prophet, peace be upon him: "The covenant between us and them is prayer; whoever abandons it has disbelieved." According to this view, one who abandons prayer must repent sincerely, increase in seeking forgiveness, and give charity, and he is not required to make up the missed prayers or fasts. Nevertheless, making up missed prayers and fasts is more prudent to avoid disagreement, as making them up is the opinion of most scholars.