Verily, the vigil of the night impresses the minds most strongly, and the speech is most upright. (Mutual consultation with your companions is more effectively done at night)
Surely the getting up at night for prayer is most effective for controlling the self and most suitable for reciting the Qur’an as well
Dr. Munir Munshey
Indeed, during the (pre dawn) hours of the night, the perception is keener and the speech more effective (and clearer)
Dr. Kamal Omar
Without doubt, the rising up during the night (from sleep): this (is) more potent an exercise (for training the Nafs or Ruh) and more retaining for the statement (or Message recited from the Scripture)
Verily, getting up at night (for Prayer) is the most effective means of subduing (one's self), and the most upright way to acquire firm control over one's actions and speech
No doubt rising at night strictly subdues (the ill-commanding self), and makes the tongue deliver straight and clear speech (with the concentration of head and heart)
Verily, the rising by night (for Tahajjud prayer) is very hard and most potent and good for governing (the soul), and most suitable for (understanding) the Word (of Allah)
Arising in the night gives greater perception and clarity in the evaluation of the call!
Al-muntakhab fi tafsir al-Qur'an al-Karim
The Calm and silence of the dead hours of the night make the soul sensible to the presence of Allah and impress piety upon one's heart and bring on that wisdom which the Divine hand imprints in his works