1646. Reported `Amr bin Shu`aib, on the authority of his father and grandfather that the Prophet (PBUH) said, "Do not pluck out grey hair, for they are the Muslim's light on the Day of Resurrection.''
[Abu Dawud, At-Tirmidhi and An-Nasa'i].

Commentary:  Plucking of gray hair, usually a sign of old age, should be avoided because besides the benefit which one gets from them in the Afterlife, they are a means of respect in this world.

1647. `Aishah (May Allah be pleased with her) said: The Messenger of Allah (PBUH) said, "He who does something contrary to our way (i.e., Islam) will have it rejected.''
[Muslim].

Commentary:  "Contrary to our way'' means such acts which have neither been allowed or justified nor can be justified by any principle of Shari`ah. Thus, this Hadith makes it abundantly clear that all heresies and violations of Shari`ah will not be accepted by Allah. Every Muslim is required to be a faithful follower of Divine orders rather than a heretic and a rebel.