Evidence from the Qur'an that the one who abandons prayer is a disbeliever and an apostate.

The Shaykh : For this reason, the one who abandons it is a disbeliever in a disbelief that expels him from the religion, meaning he becomes an apostate to whom the rulings of apostates apply in this world and the Hereafter. This is unlike the other pillars that follow it, such as zakah, fasting, and Hajj, for the one who abandons these three does not become a disbeliever according to the correct opinion, even though some scholars say that the one who abandons any pillar of Islam becomes a disbeliever. However, the correct view is that one does not become a disbeliever except by abandoning prayer. The evidence for this is from the Book of Allah, the Sunnah of His Messenger, the sayings of the Companions (may Allah be pleased with them), and correct reasoning. As for the Book, Allah the Blessed and Exalted said: meaning the polytheists The aspect of evidence from the verse is that Allah made three conditions for brotherhood in religion: the first is repentance from shirk, the second is establishing prayer, and the third is giving zakah. The implication is that if these three conditions are not fulfilled, one is not our brother in the religion of Allah. Religious brotherhood is not negated except by disbelief that expels one from the religion. As for disbelief less than that, no matter how great it is, it does not negate faith-based brotherhood. This is indicated by the fact that the greatest of sins after disbelief is killing a soul without right, yet if a person kills someone intentionally, he does not become a disbeliever for that, due to the saying of Allah the Exalted: Thus, Allah made the killer a brother to the killed, even though he committed this great crime. And He said: Thus, Allah made the two warring factions brothers to the third faction that mediates between them. This indicates that they do not exit from faith. The important point is that the saying of Allah the Exalted: indicates that if they do not do so, they are not our brothers in religion, and religious brotherhood is not negated except by completely exiting Islam.
There remains an issue with this argument, which is that abandoning zakah does not necessitate disbelief that expels one from the religion, and it is included within the condition. It is said that abandoning zakah has exited from being [a cause of disbelief] by the evidence of the Sunnah, which is in the saying of the Prophet (peace and blessings be upon him): This indicates that the one who withholds zakah does not become a disbeliever, because if he were a disbeliever, he would have no way to Paradise.