What is the reward for performing the night vigil (Qiyam al-Layl)?

Night prayer (Qiyam al-Layl) is a confirmed Sunnah, urged by texts from the Qur’an and Sunnah, due to its great importance in strengthening faith and assisting the Muslim in good deeds. It is one of the characteristics of the righteous (Muttaqeen) that Allah Almighty mentioned in His Book. Night prayer expiates sins, prevents wrongdoing, and is the practice of the righteous. It makes a Muslim among the devout (qaniteen) and increases his reward.