These two verses have produced volumes of commentary. It would seem that the word , Khalifah ' means here something more than mere , successor', though some commentators say that when God declared his intention of creating Adam, He called him a Khalifah, a successor, because Adam was to be the successor of the angels who used to live upon earth before the creation of man. But other Muslim authorities interpret ' Khalifah ' as meaning a vicegerent, a deputy, a substitutea successor in the sense of one who succeeds to some high function, and they accordingly explain that Adam and David are given the designation of 'Khalifah' since each was on earth a vicegerent of God, in their guidance of men and in th.e warnings they gave as to the commands of God. It is obvious that such an interpretation could be employed to enhance the dignity and authority of the Caliph.