Ansar Al-'Adl said:

Neglecting one's prayers out of laziness does not render one a kaafir. It simply means that such a person is lacking in their emaan. It is only the khawaarij (deviated sect) that believes that sins take one out of the fold of Islam.

akhee
I do not know about that bro,
The opinion that one who does not pray is not kaafir is the view from Abu Haneefah, Maalik, and al-Shaafa'i, and is indicated by the hadeeth of ‘Ubaadah ibn al-Saamit, who reported that the Prophet (peace and blessings of Allaah be upon him) said: “There are five prayers which Allaah has prescribed for His slave during the day and night, whoever does them and does not wilfully neglect them, Allaah will be bound to grant him admittance to Paradise. Whoever does not do them will have no such guarantee; if He wills, He will punish him and if He wills, He will grant him admittance to Paradise.” (Reported by al-Daarimi, 1531; Maalik, al-Muwatta’, 248; Ahmad, 21690).
The opinion that the one who does not pray is a kaafir is the opinion narrated from ‘Umar, ‘Ali and Ibn Mas’ood (may Allaah be pleased with them). It was also the opinion of al-Hasan, al-Sha’bi, al-Oozaa’i, Ibn al-Mubaarak and Muhammad ibn al-Hasan; it was also reported from Ahmad, and is indicated by the hadeeth of the Prophet (peace and blessings of Allaah be upon him),
“All that stands between a person and kufr is his not praying.” (Reported by Muslim, Ahmad, Abu Dawood and Ibn Maajah).
The evidence lies more in the first opinion. The first evidence is the ayaah:
“But if they repent [by rejecting Shirk (polytheism) and accept Islamic Monotheism], perform As-Salaat (Iqaamat-as-Salaat) and give Zakaat, then they are your brethren in religion.” [al-Tawbah 9:11]
In Risaalah fi Hukm Taarik al-Salaah (Paper on the ruling on one who neglects the prayer), Shaykh Uthaymeen writes:
The evidence derived from this aayah is that Allaah defined three things that the Mushrikeen have to do in order to eliminate the differences between them us: they should repent from shirk, they should perform prayer, and they should pay zakaah. If they repent from shirk but they do not perform the prayer or pay zakaah, then they are not our brethren in faith; if they perform the prayer but do not pay zakaah, then they are not our brethren in faith. Brotherhood in religion cannot be effaced except when a person goes out of the religion completely; it cannot be effaced by fisq (immoral conduct) or lesser types of kufr.
Allaah also says (interpretation of the meaning):
“Then, there has succeeded them a posterity who have given up As-Salaat (the prayers) [i.e. made their Salaat (prayers) to be lost, either by not offering them or by not offering them perfectly or by not offering them in their proper fixed times] and have followed lusts. So they will be thrown in Hell. Except those who repent and believe (in the Oneness of Allaah and His Messenger Muhammad), and work righteousness. Such will enter Paradise and they will not be wronged in aught.” [Maryam 19:59-60]
The evidence derived from this aayah is that Allaah referred to those who neglect the prayer and follow their desires, Except those who repent and believe, which indicates that at the time when they are neglecting their prayers and following their desires, they are not believers.
The evidence of the Sunnah that proves that the one who neglects the prayer is a kaafir includes the hadeeth of the Prophet (peace and blessings of Allaah be upon him):
“Between a man and shirk and kufr there stands his neglect of the prayer.” (Narrated by Muslim in Kitaab al-Eemaan from Jaabir ibn ‘Abd-Allaah from the Prophet (peace and blessings of Allaah be upon him)).
It was narrated that Buraydah ibn al-Husayb (may Allaah be pleased with him) said: “I heard the Messenger of Allaah (peace and blessings of Allaah be upon him) say: ‘The covenant that distinguishes between us and them is the prayer, and whoever neglects it has disbelieved (become a kaafir).’” (It was narrated by Ahmad, Abu Dawood, al-Tirmidhi, al-Nisaa’i and Ibn Maajah).
What is meant here by kufr or disbelief is the kind of kufr which puts a person beyond the pale of Islam, because the Prophet (peace and blessings of Allaah be upon him) made prayer the dividing line between the believers and the disbelievers. It is known that the community of kufr is not the same as the community of Islam, so whoever does not fulfil this covenant must be one of the kaafireen (disbelievers).
There is also the hadeeth of ‘Awf ibn Maalik (may Allaah be pleased with him), according to which the Prophet (peace and blessings of Allaah be upon him) said:
“The best of your leaders are those whom you love and who love you, who pray for you and you pray for them. The worst of your leaders are those whom you hate and who hate you, and you send curses on them and they send curses on you.” He was asked, “O Messenger of Allaah, should we not fight them by the sword?” He said, “Not as long as they are establishing prayer amongst you.”
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