There is no special physical significance in the remains of the Prophets or relics of Their Persons. But there is a profound spiritual significance in the sense that Their dust was the physical mirror of the greatness of God. In other words we know God through His Prophets, Who have bodies; these bodies -- Their very dust -- are precious through association. It is natural for people to be touched by a lock of hair or some token of one they loved; how much more should we treasure and feel moved by a relic of the Beloved of God? …
The atoms of the Prophets are just atoms, like all others, but the association of this great spiritual power with them leaves in the place they are laid to rest a spiritual atmosphere, if one can use this expression. They are, no doubt, endowed with a tremendous spiritual influence and far-reaching power. But the physical character of their atoms are not different from other people's, any more than their bodies and physical functions are different.
- Shoghi Effendi (From a letter written on behalf of Shoghi Effendi; ‘Directives from the Guardian’)