He abandoned the Prayer throughout his Time in the University

Question :

A young, sane, Muslim man used to pray before he entered the University, then he abandoned prayer during his time there which was four years then he repented and returned to prayer after his graduation from the University. What is the ruling on the four years during which he abandoned prayer, bearing in mind that he did not deny the obligation of prayer? Should he make up the prayer for the four years which he missed or is repentance sufficient?

Answer:

The correct opinion from among the sayings of the scholars as we know it is that whoever abandons prayer deliberately, does not make up for what he has missed of it, based upon the Words of Allah, the Most High:
Verily, the prayer is enjoined on the believers at fixed hours.

Allah, the Most Glorified has said that the obligatory prayer is enjoined at fixed times and these times have been made clear to the Prophet by Jibril, upon him be peace, during the night of Al-Mi'raj and the Prophet established their times for his community, by deed and word. Therefore, it is not permissible to advance the prayer to before its set time, nor to delay it, nor is it correct (if done that way). And because the correct opinion from among the sayings of the scholars as we see it is that one who abandons prayer is a disbeliever, then if he repents, there is no need to make up for the fixed acts of worship which he missed during the days of his disbelief. And if he is true in his repentance, then it is preferred for him to do good, and that he perform many righteous deeds and lots of supererogatory prayers. This is supported by what is understood from the words of the Prophet
Whoever slept through a prayer or forgot it, must make up for it as soon as he remembers it, and there is no expiation for it except this.

What is understood from this is that one who intentionally abandons the prayer does not fall into these categories, so it is not correct to compare the one who intentionally leaves prayer with the sleeper or the one who forgets, because the one who leaves it intentionally is not excused and Allah has not made for him another time in which he can make up for what he has missed, while the sleeper and the one who forgets are excused, and Allah has made for them another time in which to make up for what they have missed.

And through Allah is attained success. And may peace and blessings be upon our Prophet, Muhammad and upon his family and Companions.

Source:
The Permanent Committee
Fatawa Islamiyah, Vol. 2 Pages 378-379-380