On the matter of supplication, His Majesty takes note that also in related to it is food, as in the Hadits narrated by Muslim which tells about a man who has travelled far until his hair was unkempt, filled with dust, then he raised his hands and supplicated: "O my God! O my God!" But his food and drink are from haram sources, thus how will Allah accept his supplication?
Source: Radio Television Brunei