Translation:

6. Truly the rising by night is most potent for governing (the soul) and most suitable for (framing) the Word (of Prayer and Praise).

Notes (Tafseer)

5758. For contemplation, prayer, and praise, what time can be so suitable as the night, when calm and silence prevail, the voices of the market-place are still, and the silent stars pour forth their eloquence to the discerning soul.