On the authority of 'Abdullaah, who related that he heard the Messenger of Allaah (sal-Allaahu `alayhe wa sallam) say:

((Whoever makes the Hereafter his sole concern, then Allaah will be sufficient for him concerning his affairs and needs in the world, and whoever's concerns are divided amongst the affairs of the world, then Allaah would have no care in which path he is destroyed)).

Reported by Ibn Maajah and others. Authenticated by Shaykh al-Albaanee in al-Mishkaat.

Ref: Fatwa-Online

Shaykh Abdul-Azeez ibn Baaz said:

"It has been narrated that al-Hajar al-Aswad descended from Paradise white, then it became black due to the sins of Ahlush-Shirk..."

Ref: Origin of the Black Stone