Qiyam al-Layl, "standing the night", is the broad Islamic devotion of spending part of the night in voluntary prayer, and the general category within which the more specific night practices fall. It embraces the extended standing recitation of the Qur'an, the units of voluntary prayer offered in the darkness, supplication, and the remembrance of God, undertaken in the hours when others sleep. The Qur'an repeatedly commends those who pass the night in prostration and standing before their Lord, and holds up the night vigil as a mark of the sincere servant, harder to sustain than daytime devotion and therefore of greater worth.
The practice overlaps closely with tahajjud, the vigil kept after a period of sleep, and reaches its most intense communal form in the tarawih and the special night prayers of Ramadan, above all in the sought-after Night of Power in the last ten days of the month, which the Qur'an declares better than a thousand months. Outside these appointed times, standing the night remains an open field for personal devotion, unregulated by congregation and undertaken according to each believer's capacity and zeal. The Sufi traditions especially cultivated it as the private engine of the spiritual life, and the tradition as a whole treats a share of the night given to prayer as among the surest means of drawing near to God.