Tafsir of Al-Muzzammil 73:7

{...a prolonged occupation} It means movement and activity in your tasks and preoccupations. You are not free except at night; therefore, you must engage in private communion with God, which requires a clear mind and the absence of distractions.

As for the reading with a kha (sabkhan), it is a metaphor derived from the carding of wool (sabkh al-suf), which is the fluffing and spreading of its parts. This is due to the scattering of concerns and the distraction of the heart by preoccupations.

He commanded him to perform the night prayer, then mentioned the wisdom behind it:

• It is more conducive to agreement (between the heart and the tongue).
• It is more effective for recitation due to the stillness of the body and the lowering of voices.
• It is more gathering for the heart and more restrictive of the scattering of concerns compared to the day. The day is a time for the dispersion of worries, the distribution of thoughts, and movement for the needs of livelihood and the afterlife.

It is also said: It means leisure and space for your sleep and your movement in your needs.

It is also said: If you miss anything during the night, you have leisure during the day in which you are able to make up for it.

{And remember the name of your Lord and devote yourself to Him with [complete] devotion. [He is] the Lord of the East and the West; there is no deity except Him, so take Him as Disposer of [your] affairs. And be patient over what they say and avoid them with gracious avoidance.}