How can one respond to those who quote narrations from Ibn Taymiyyah's book "Al-Kalim Al-Tayyib" which mention that Ibn 'Umar and Ibn 'Abbas commanded to mention the name "Muhammad" when a man's leg goes numb, while we prohibit mentioning human beings in tawassul (seeking intercession) and the like, and how could Ibn Taymiyyah mention these narrations without authentication or weakening, given that he was among the foremost in opposing such matters?

The mentioned narration is weak, due to dissimulation (tadlis) and confusion (ikhtilat) within its chain. As for the narration from Mujahid, it is fabricated. Even if the narration were authentic, it does not provide evidence for the permissibility of seeking help from other than Allah (istighatha bi ghayr Allah) or invoking the absent (du'a al-gha'ib). Rather, it falls under the category of medical treatment and pure customs prevalent among Arabs. Ibn Taymiyyah's mention of it was from this perspective, not from the perspective of seeking intercession (tawassul).