of disbelief. Hypocrisy can be partial, and disbelief can be partial and can increase and decrease, just as faith can be partial and can increase and decrease. Allah Most High says:

“Postponement of the sacred months is only an increase in disbelief.”

And He says:

“Whenever a surah is revealed, some of them say, ‘Which of you has this increased in faith?’ As for those who believe, it increases them in faith, and they rejoice.”

“But as for those in whose hearts is disease, it adds impurity to their impurity, and they die as disbelievers.”

And He says:

“We send down of the Quran that which is healing and mercy for the believers, but it only increases the wrongdoers in loss.”

And He says:

“What has been sent down to you from your Lord will surely increase many of them in transgression and disbelief.”

And He says:

“Allah increases those who are guided in guidance.”

And He says:

“In their hearts is a disease, so Allah has increased their disease.”

And He says:

“Indeed, those who believed, then disbelieved, then believed, then disbelieved, and then increased in disbelief.”

Many authors on speculative theology refute the People of the Book only on matters they say can be known through reason, such as the Christian doctrine of the Trinity and their rejection of Muhammad. They do not debate them concerning other fundamentals of religion. This is a shortcoming on their part and a departure from the Quran’s approach. For Allah explains in the Quran how they contradicted the prophets and censures them for doing so; the Quran is filled with such passages. Since disbelief and faith concern messengership and prophethood, once the ways in which they contradicted the prophets become clear, their disbelief becomes evident.