Is the Muslim who commits unlawful sexual intercourse considered a disbeliever?
All perfect praise be to Allaah, the Lord of the worlds. I testify that there is none worthy of worship except Allaah and that Muhammad, sallallaahu ‘alayhi wa sallam, is His slave and Messenger.
Indeed, Zina (adultery/fornication) is a grave sin for which Allaah, the Exalted, prescribed a Hadd (corporal punishment prescribed by the Sharee'ah for a certain crime) in this worldly life, or in the Hereafter—for those who die without repenting from that sin. However, committing Zina is not considered an act of disbelief that takes one out of the fold of Islam, unless the doer believes that it is lawful. This is because committing Zina is a sin, and committing sins does not constitute disbelief. This is contrary to the beliefs of the Khawarij and those who followed their example. As for Ahlus-Sunnah Wal-Jamaa‘ah, Imaam At-Tahawi underlined their attitude toward this issue as he said, "We do not believe any Muslim is considered a disbeliever for committing a sin, unless he believes that it is lawful." [Al-‘Aqeedah At-Tahawiyyah]
Allaah Knows best.
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