Dying of thirst!

David and Willson were lost in desert...they were dying of thirst when they came upon an oasis, and there was a Mosque.

David to Willson:
"Look there is a mosque, lets pretend we are muslims, otherwise we'll not get any food or water...I am going to call myself 'Ahmad". Willson refused to change his name and said:
"my name is Willson and i will never pretend to be other than but what I am!"
...
The Imam of mosque recieved both well and asked their names...

David:
am Ahmad

Willson:
am Willson

Imam turned to his helpers and said:
"bring some food for Willson only"

And then Imam turned towards David and said:
"Ramdan Mubarak Brother Ahmad!"