370. hadíth
وَ إِنَّمَا أُمِرَ بِرَمْيِ اَلْجِمَارِ لِأَنَّ إِبْلِيسَ اَللَّعِينَ كَانَ يَتَرَاءَى لِإِبْرَاهِيمَ عَلَيْهِ اَلسَّلاَمُ فِي مَوْضِعِ اَلْجِمَارِ فَيَرْجُمُهُ إِبْرَاهِيمُ عَلَيْهِ اَلسَّلاَمُ فَجَرَتْ بِذَلِكَ اَلسُّنَّةُ » وَ رُوِيَ «أَنَّ أَوَّلَ مَنْ رَمَى اَلْجِمَارَ، آدَمُ عَلَيْهِ اَلسَّلاَمُ ثُمَّ إِبْرَاهِيمُ عَلَيْهِ اَلسَّلاَمُ ».
The command to throw the pebbles (Ramy al-Jamarat) was given because Iblis, the accursed, would appear to Ibrahim (a.s) at the locations of the Jamarat, and Ibrahim (a.s) would pelt him with stones. Thus, it became a tradition. It has also been narrated that the first to throw the pebbles was Adam (a.s) followed by Ibrahim, peace be upon him.