faqih-677Vol. 1, p. 227
لَهُ- زَوَالُ الشَّمْسِ نَعْرِفُهُ بِالنَّهَارِ كَيْفَ لَنَا بِاللَّيْلِ فَقَالَ لِلَّيْلِ زَوَالٌ كَزَوَالِ الشَّمْسِ قَالَ فَبِأَيِّ شَيْءٍ نَعْرِفُهُ قَالَ بِالنُّجُومِ إِذَا انْحَدَرَتْ[2].
Hadith.678 - Umar ibn Hanthala asked Imam Jafar ibn Muhammad Al-Sadiq (as) saying: "We recognize the zenith (midday) of the sun during the day; how can we recognize the zenith during the night?" Imam (as) said: "The night has a zenith just like the zenith of the sun." Umar then asked: "And by what means do we recognize