Did the Prophet, peace and blessings be upon him, dye his hair and beard with henna, and is it permissible for a man to dye his hair and beard without the presence of gray hairs?

The Prophet, peace and blessings be upon him, dyed his hair with henna and katam, and many hadiths have been narrated to that effect. As for what is reported from Anas that he did not dye his hair, it is contradicted by what has been advanced from others affirming it. The one who affirms it possesses additional knowledge not present with the one who negates it. The preferred view is that he dyed it at certain times and left it undyed most of the time. As for dyeing hair, even if there is no grayness, there is no impediment to it due to the general reports concerning dyeing.