Sayyiduna Rafi' bin Khadij (may Allah be pleased with him) said: I saw a thread (tied) on the hand of the Prophet (peace and blessings be upon him), so I asked: What is this for? He (peace and blessings be upon him) said: I remember things by means of it.
Al-Tabarani recorded it in al-Mu'jam al-Kabir; its chain contains Ghiyath bin Ibrahim, who is extremely da'if (weak).
Hadith Referenceمجمع الزوائد ومنبع الفوائد / كتاب العلم / 757
Hadith Gradingمحدثین:إسنادہ ضعیف جداً۔
Hadith Takhrij«اخرجه الامام الطبراني فى معجمه الكبير 4430 ، أخرجه المعجم الكبير للطبراني برقم: 4430»