The following is from a work-in-progress called The Qur'an: a Book Report, in which I read each surah of the Qur'an and write about what I learn.
This is Meccan surah which takes its title from the opening line, which is a reference to the apocalyptic Day of Resurrection: “When the sky cracks, obeying its Lord as it rightly must, when the earth is leveled out, casts out its content and becomes empty, obeying its Lord as it righty must…” The obedience of nature is contrasted with the disobedience of the unbelievers: “So why do they not believe? Why, when the Qur’an is read to them, do they not prostrate themselves [to God]?”