Islam teaches that life after death is a continuation of existence, marked by accountability and eternal consequences. This belief is a fundamental pillar of faith.
Upon death, the soul of a believer is returned to their body in the grave. There, two angels, Munkar and Nakir, will question them about their Lord, religion, and Prophet. A believer who is firm in their faith will respond: "My Lord is Allah, my religion is Islam, and my Prophet is Muhammad (peace be upon him)." This is a test, and God strengthens believers with a firm saying in this life and the Hereafter (Quran 14:27). As a result, their grave is expanded and beautified, a door to Paradise is opened, and its pleasant fragrance fills the space (Beğavî — Meâlimü't-Tenzîl, s. V04/P350–V04/P352; Abdülkâdir Geylânî — el-Gunye, s. V01/P143–V01/P145; İbn Kesîr — Tefsîrü'l-Kur'âni'l-Azîm, s. V03/P411–V03/P412; Ebû Dâvûd — Sünen, s. V04/P238–V04/P240; Taberî — Câmiü'l-Beyân, s. V13/P657). A righteous person will be greeted by a figure representing their good deeds, bringing them glad tidings.
Conversely, a disbeliever will be unable to answer the angels' questions, and a caller from the sky will announce their falsehood. Their grave will be constricted, a door to Hellfire will be opened, and they will be visited by a figure representing their evil deeds, informing them of their punishment (Abdülkâdir Geylânî — el-Gunye, s. V01/P143–V01/P145; İbn Kesîr — Tefsîrü'l-Kur'âni'l-Azîm, s. V03/P411–V03/P412; Ebû Dâvûd — Sünen, s. V04/P238–V04/P240).
The grave is understood as a barzakh, an intermediary state between this world and the Hereafter (İmam Rabbânî — Mektûbât, s. V01/P350–V01/P352). Both the righteous and the wicked experience comfort or torment in this state, which is a reality to be believed in, even if its exact nature is beyond human comprehension (Gazâlî — Kavâidü'l-Akâid, s. V01/P219–V01/P229).
Islam also affirms the Day of Judgment (Yawm al-Qiyamah), when all will be resurrected and held accountable for their actions. This will be followed by an eternal existence in either Paradise (Jannah) or Hellfire (Jahannam) (Abdülkâdir Geylânî — el-Gunye, s. V01/P145–V01/P146; Gazâlî — Kavâidü'l-Akâid, s. V01/P219–V01/P229). The Quran emphasizes this certainty: "And the Hour is coming, no doubt about it, and Allah will resurrect those who are in the graves" (Quran 22:7).
These teachings are based on the Quran and the Sunnah (teachings and practices of Prophet Muhammad, peace be upon him), as narrated in authentic hadith collections and elaborated upon by scholars.