قَالُوا۟ يَـٰٓأَبَانَآ إِنَّا ذَهَبْنَا نَسْتَبِقُ وَتَرَكْنَا يُوسُفَ عِندَ مَتَـٰعِنَا فَأَكَلَهُ ٱلذِّئْبُ ۖ وَمَآ أَنتَ بِمُؤْمِنٍ لَّنَا وَلَوْ كُنَّا صَـٰدِقِينَ Qur’an Yusuf (12:17)Q a loo y a ab a n a inn a th ahabn a nastabiqu watarakn a yoosufa AAinda mat a AAin a faakalahu a l thth ibu wam a anta bimuminin lan a walaw kunn a sa diqeen a
They were surprised that Jacob received the story about the wolf with cold incredulity. So they grew petulant, put on an air of injured innocence, and bring out the blood-stained garment described in the next verse.
They wanted to make out that they were not negligent of Joseph. They were naturally having games and exercise, while the boy was left with their belongings. It was the racing that prevented them from seeing the wolf. And Jacob's fears about the wolf (xii. 13 above) made them imagine that he would swallow the wolf story readily.