Tafsir of Az-Zumar 39:69

God—Exalted is His Majesty—has metaphorically used "light" to represent Truth, the Quran, and Proof in various places in the Revelation; this is one of those instances.

The meaning is: "The earth will shine" through the Truth and Justice He establishes upon it, and the equity He spreads in the reckoning and the weighing of good and evil deeds.

The attribution of this light to His Name is metaphorical, for He is the Truth and the Just. The attribution of His Name to the earth is because He adorns it by spreading His justice, setting up the scales of His equity, and judging between its inhabitants with Truth. There is nothing more beautiful for a land than justice, nor anything that makes it more prosperous. This attribution signifies that its Lord and Creator is the One who judges justly within it, whereas any other than its Lord would only permit injustice.

The events that follow the shining of the earth—the placing of the Book, the arrival of the prophets and the witnesses, and the judgment with Truth—are all part of this aforementioned "light."

You see people say to a just king: "The horizons have shone with your justice, and the world has been illuminated by your equity," just as you say: "The lands have darkened with the tyranny of so-and-so." The Messenger of God (peace be upon him) said: "Injustice is darkness on the Day of Resurrection." Just as He opened the verse by establishing justice, He concluded it by negating injustice.

It has been recited as ushriqat (passive voice), derived from shariqat bi-ḍ-ḍaw’ (it became filled and saturated with light). God caused it to shine, just as one says: "He filled the earth with justice and covered it with justice."

• "The Book": The scrolls of deeds, though the generic noun is used. It is also said to be the Preserved Tablet (al-lawḥ al-maḥfūẓ).
• "The Witnesses": Those who testify for and against the nations, consisting of the recording angels and the righteous. It is also said to be those who were martyred in the way of God.

"And those who disbelieved will be driven to Hell in groups, until, when they reach it, its gates are opened and its keepers will say to them, 'Did there not come to you messengers from yourselves, reciting to you the verses of your Lord and warning you of the meeting of this Day of yours?' They will say, 'Yes, but the word of punishment has come into effect upon the disbelievers.' [It will be] said, 'Enter the gates of Hell to abide eternally therein, and wretched is the residence of the arrogant.'"