"So they pursued them at sunrise," meaning: when the sun rose; he returns to the beginning of the story.
﴿فأتبعوهم مشرقين﴾ يَعْنِي: حِينَ أَشْرَقَتِ الشَّمْسُ؛ رَجَعَ إِلَى أَوَّلِ الْقِصَّةِ.
