There was a monk in Syria (Sham). The Christians glorified and magnified the monk. The monk preached to them once a year. Imam Musa met him on that day when he was surrounded by monks and people. When the Imam sat down, the monk turned to him and asked him:
-Fellow, are you a stranger?
-Are you from us or against us?
-I am not from you.
-Are you from the community upon which (Allah) has mercy?
-Are you from among its scholars or from among its ignorant?
-I am not from among its ignorant.
The monk became confused and began to ask the Imam about the most difficult questions he had, saying:
-How is that the origin of the Tree of Tuba is with us, in the Abode of Isa (Jesus), with you, in the Abode of Muhammed, may Allah bless him and his family, and its branches are in every house?
-It is just like the sun whose light reaches every place and situation while it is in the heaven.
-Why does the food in the Garden not run out and not decrease even though they eat of it?
-It is just like the lamp in the world from which (men) take fire while it does not decrease.
-What is the extended shade in the Garden?
-The time before the sunrise is the extended shade. Then he recited these words of Him the Exalted: “Have you not considered (the work of) your Lord, how He extends the shade?”
-Why do the inhabitants of the Garden not relieve the nature while they eat and drink?
-They are just like the embero in its mother’s womb.
-How do the servants in the Garden serve its inhabitants without being ordered?
-When man is in need of a thing, his limbs know that, so the servants know that and carry it out without being ordered.
-Are the keys of the Garden (made) of gold or silver?
-The keys of the Garden are the servant’s words: “There is no god but Allah!”
-You are right!
Then the monk and his people became Muslims. ( Al-Manaqib, vol. 3, p. 427. )