Sahih Bukhari

Narrated Sa`id bin Jubair:I was with Ibn `Umar when a spear head pierced the sole of his foot and his foot stuck to the paddle of the saddle and I got down and pulled his foot out, and that happened in Mina. Al-Hajjaj got the news and came to inquire about his health and said, ""Alas! If we could only know the man who wounded you!"" Ibn `Umar said, ""You are the one who wounded me."" Al-Hajjaj said, ""How is that?"" Ibn `Umar said, ""You have allowed the arms to be carried on a day on which nobody used to carry them and you allowed arms to be carried in the Haram even though it was not allowed before