Chapter on Times of Prayer and Sign of Each of Its Times

And from him, from Muhammad ibn Yahya, from Salamah ibn al-Khattab, from Ali ibn Sayf ibn ‘Umayrah, from his father, from ‘Umar ibn Hanzalah, from Abu Abdillah عليه السلام, who said: (Imam عليه السلام said) “When the sun passes the meridian, the time for Dhuhr has entered, except that there is a supererogatory prayer before it, and that is up to you, if you wish, you may lengthen it, and if you wish, you may shorten it.”