If a person who is either born in or converted to Islam, doesn't want to follow the fundamentals (five pillars e.g Imaan, Namaz, Roza, Zakat, and Hajj) of Islam, then what will happen, what our prophet said about that person?
Muslims have agreed that whoever does not perform (recite) it is an infidel
(Ibn Taymiyyah - the book of Faith)
- Salah (Namaz): Prophet Mohammad (PBUH) said:
The covenant between us and them is prayer, so if anyone abandons it he has become an infidel
The rest, Sawm (fasting), Zakat and Hajj scholars differed in the one who left them while not deniying them to be obligatory some said he becomes an infidel.
On the other hand, anyone who denies any of the 5 pillars to be obligatory, leaves Islam because he then rejects the clear commands of Allah and his prophet.
The prophet (PBUH) said:
Islam is built on five things: the testimony that there is no god but God and that Muhammad is His servant and messenger, the observance of the prayer, the payment of zakat, the Pilgrimage, and the fast during Ramadan.
Notice: the Prophet PBUH chose the word built, so think, if a building gets any of its pillars broken, most probably the rest will fail too.