Tafsir of At-Tariq 86:11-14

"By the sky which returns" Rain is called raj‘ (return), just as it is called awb (return). A poet said: A high, towering mountain, to whose summit None resort but the clouds, the returning rain, and the downpour.

It is named using the verbal nouns raj‘ and awb. This is because the Arabs used to claim that the clouds carry water from the earth’s seas and then return it to the earth. Or, they intended an omen by naming it raj‘ and awb so that it would return and come back. It is also said: because God returns it time after time. Al-Khansā’ said: "Like the rain in the night-traveling storm cloud."

"And the earth which splits" Ṣad‘ (splitting) refers to the vegetation that causes the earth to split open.

"Indeed, it is a decisive word" The pronoun refers to the Qur’an. It is a separator between truth and falsehood, just as it is called Furqān (the Criterion).

"And it is not for amusement" Meaning, it is entirely serious, with no room for levity. Since God has described it as such, it is its due that it be held in awe in the breasts, magnified in the hearts, and that its reader and listener be elevated by it. It is not fitting that it be approached with jest or treated with humor. One should direct their mind to the fact that the Compeller of the heavens is addressing them, commanding them, forbidding them, promising them, and threatening them. Even if fear does not stir them and awe does not reach its peak in them, the minimum requirement is that they be serious, not mocking. God has condemned the polytheists for this in His saying: "And you laugh and do not weep, while you are heedless" (An-Najm: 60–61), and "And speak noisily therein" (Fuṣṣilat: 26).

"Indeed, they are planning a plan, but I am planning a plan. So grant the disbelievers respite; leave them for a little while."