It is narrated from Sayyiduna Jabir bin Abdullah (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said: Goodness and benefit will remain attached to the foreheads of horses until the Day of Resurrection, and their owners endure hardships while riding them. Therefore, touch the foreheads of horses and pray for blessings for them, and put collars on them, but they should not be made of hemp.
Hadith Takhrij«حسن لغيره، أخرجه الطبراني في الاوسط : 8977 ، (انظر مسند أحمد ترقيم الرسالة: 14791 ترقیم بيت الأفكار الدولية: 14851»
Brief Explanation
Benefits: … There can be three reasons for the prohibition of a necklace made of fiber: (1) While running or grazing, it can cause strangulation, leading to suffocation; (2) such a fiber was hung around the necks of horses to protect them from the evil eye and various harms; and (3) this fiber is hard and sharp, which poses a risk of cutting the throat.