Tafsir of Al-Qamar 54:11

Meaning: pouring down. It is also said: abundant. A poet said: "O my two eyes, pour forth tears (that are flowing) for the best of all people, whether nomadic or sedentary."

The ba (in bi-ma'in) is for instrumentality, similar to its usage in "I opened the door with the key." It is also permitted that it denotes accompaniment (mulabasa), but the former is more emphatic. In the expression, there is a tashbih tamthili (allegorical metaphor) comparing the flow of rain from the clouds to the pouring of rivers, as if the gates of heaven were opened by it, causing the expanse of the sky to split. This is the position held by the majority.

A group held that it is to be taken literally, which is the apparent meaning of the words of Ibn Abbas. Ibn al-Mundhir and Ibn Abi Hatim recorded that he said: "The sky never rained before that day, nor after it, except from clouds. But on that day, the gates of heaven were opened with water without clouds, and the two waters met." In one narration: "It did not cease for forty days."

Al-Naqqash suggested that the "gates" refer to the Galaxy (al-majara), which is the seam (sharj) of the sky, like the seam of a leather bag. It is known from astronomical observations that the Galaxy consists of very small, closely clustered stars. And Allah, the Exalted, knows best.

It is a matter of wonder that they had been seeking rain for years, so Allah, the Exalted, destroyed them with what they had sought.

Ibn Amir, Abu Ja'far, al-A'raj, and Ya'qub read it as fattaḥnā (with tashdid), to signify the multitude of the gates. It is apparent that the plural form here denotes a large number.