they fall down in prostration—the very prostration they perform during the ritual prayer. This is a sequenced act: first they move to bowing, then to prostration. The prostration itself is performed twice, as the Messenger clarified, so that two descents are joined in it: a descent from standing, which is the first prostration, and a descent from sitting, which is the second. From this the obligation of the separating sitting (qaʿdat al-fasl) and of remaining calm in it is inferred, in accordance with the Sunnah, for a fall into prostration can issue only from a sitting or a standing posture. If the interval between the two prostrations is as thin as a sword’s edge, or closer to sitting than to standing, it is no longer considered a fall.

The one who allows such haste imagines that prostration is achieved merely by placing the head on the ground in whatever manner; that is not so. Rather, one is commanded to fall, as He said:

“When they are reminded of it they fall down in prostration” (al-Sajdah 15),

and He did not say, “they prostrate.” The very act of falling (khurūr) is therefore enjoined, as stated in this verse, and the descent onto the chin is itself an intended act of worship, just as placing the forehead on the earth is an intended act of worship.

This is confirmed by His words:

“Say: ‘Believe in it or do not believe.’ Surely those who were granted knowledge before it—when it is recited to them, they fall upon their chins in prostration and say, ‘Glory be to our Lord! The promise of our Lord has indeed come to pass.’ And they fall upon their chins weeping, and it increases them in humility.” (al-Isrāʾ 107–109)

He praised and commended them for falling upon their chins—that is, onto their chins—in prostration, and again for falling upon their chins—onto them—while weeping.