What is the virtue of qiyam (night prayer), and what has been reported about it in the Sunnah?

Qiyam (definition) al-Layl (standing in night prayer) is the practice of the righteous and the Sunnah (definition) of the Prophet, peace be upon him. Whoever revives it, Allah will revive his heart and enlighten his insight. Many proofs from the Quran and Sunnah indicate its virtue. From the Quran, Allah Almighty says: "Is one who is devoutly obedient during periods of the night, prostrating and standing, fearing the Hereafter and hoping for the mercy of his Lord, [like one who does not]? Say, 'Are those who know equal to those who do not know?' Only those of understanding will remember." (Quran 39:9). And His saying, the Almighty: "Their sides forsake their beds; they supplicate their Lord in fear and aspiration, and from what We have provided them, they spend." (Quran 32:16). And His saying, the Almighty: "and those who ask forgiveness before dawn." (Quran 3:17). From the Sunnah, the hadith (definition) of Abdullah ibn Salam, may Allah be pleased with him, states that the Prophet, peace be upon him, said: "O people, spread peace, feed the hungry, and pray at night while people are asleep, and you will enter Paradise in peace." And the hadith of Abu Hurairah, may Allah be pleased with him, states that the Prophet, peace be upon him, said: "The best fasting after Ramadan (definition) is Allah's month of Muharram, and the best prayer after the obligatory prayers is the night prayer."