إِذَا غَابَ الْهِلَالُ قَبْلَ الشَّفَقِ فَهُوَ لِلَيْلَتِهِ وَ إِذَا غَابَ بَعْدَ الشَّفَقِ فَهُوَ لِلَيْلَتَيْنِ.
“Abu ‘Abd Allah (a.s.), has said, ‘If the crescent disappears before al-Shafaq (redness) it is of the first night, but if disappears after al-Shafaq it is of the second night.’”