What is the ruling of the Sharia regarding making up missed prayers for someone who abandoned prayer for a long time and then intended to commit to it, and what is the remedy for one who does not maintain their prayers or achieve khushu' (devotional humility) in them?

Scholars have differed concerning the ruling on one who abandons prayer. Some have gone to the extent of deeming it an act of disbelief that expels one from the fold of Islam, citing the Hadith (definition): "The covenant between us and them is prayer; whoever abandons it has disbelieved." According to this view, there is no make-up (qada') for the repentant person. The majority, however, hold that it is not an act of disbelief that expels one from the fold of Islam, and therefore, such a person must make up the prayers they missed. Some of them say that making up the prayers is not obligatory. The solution for one who abandons prayer is counsel, knowing that a lack of devotion does not justify abandoning it.