In another version recorded by Aḥmad, the Messenger of Allah ﷺ forbade plucking grey hairs and said, “It is light.”

This shows that the mention of dyeing in the ḥadith has no basis. For that reason al-Ḥāfiẓ [Ibn Ḥajar] said in Fatḥ al-Bārī, after citing the first wording:
“It was transmitted by al-Tirmidhī, who graded it ḥasan, and I have not seen the stated exception in any of its chains.”

I say: this can be qualified by Aḥmad’s narration, which does contain the mention of plucking.

There is a third ḥadith from which a ruling on dyeing could be inferred, owing to its unrestricted wording. It is reported from Umm Sulaym, traced back to the Prophet ﷺ: “Whoever grows a single grey hair in Islam, it will be a light for him so long as he does not change it.”

Al-Ḥākim related it in al-Kunā, as cited in al-Jāmiʿ al-Ṣaghīr, where he marked it as ḥasan, as al-Manāwī notes in his commentary. Yet the heart is not at ease with al-Suyūṭī’s grading, given his well-known lenience; see the Introduction, Principle Eight.

I later examined the isnād of the ḥadith and realized I had been right not to rely on that grading. I exposed its flaw in al-Ṣaḥīḥa under ḥadith 1244, judged it fabricated, and therefore listed it in Ḍaʿīf al-Jāmiʿ al-Ṣaghīr, no. 5651—a work filled with weak and fabricated reports, unrivalled in its kind. Allah alone grants success.

In short, it is impermissible to oppose the authentic narrations that establish the permissibility and desirability of dyeing with these weak reports. Even if one of them were sound, harmonization would still be obligatory, and the methods for reconciling ḥadiths are many. In this case one would say that the “changing” mentioned in the first and third narrations refers to plucking—explicitly forbidden in Aḥmad’s version of the second ḥadith—or to dyeing the hair black, which is likewise forbidden. Thus the matter is clarified.