108. " or do you desire to question your messenger (muhammad)
as moses was questioned aforetime ? and he
who exchanges faith for infidelity, he has surely strayed
from the right way."

occasion of revelation:

in the commentary books you may find some apparently different
occasions of revelation for this verse, but their conclusions are nearly
the same. a few of them are as follows:

one of the occasions of revelation upon the above verse has been
narrated by ibn abbas. it is stated that once wahab-ibn-zayd and
rafi`-ibn-harmalah came to the holy prophet (p.b.u.h.) and asked him
to bring a letter from allah for them to read and then they might
believe. or, it happened that he (p.b.u.h.) was asked to make some
streams appear and flow for them so that they might follow him.

some other commentators have said that a group of arabs wanted
from the prophet of islam (p.b.u.h.) the same things that the jews
wanted from moses (a.s.). they asked him to show the lord clearly so
that they could see him with their own eyes and then they would
believe.

as a response to them for their demand, the above verse was
revealed.
 

commentary :
some futile pretexts

the addressees, in this verse, are some muslims whose faith was
feeble, or the pagans. the jews are not mentioned directly in this verse
but, as we will explain later, it is not far removed from the story of the
jews.

it was, perhaps, after the event of the change of the qiblah that
some of muslims and pagans, affected by the temptations of the jews,
requested some vain and futile demands from the holy prophet
(p.b.u.h.), the examples of which were cited in the above. allah, the
almighty, forbade them to ask such questions. the qur'an says:

" or do you desire to question your messenger (muhammad) as
moses was questioned aforetime ? ..."
but you have decided, indeed, to
evade believing by the acceptance of these vain pretexts.

in view of the fact that this action is a way of exchanging faith
for blasphemy, at the end of the verse it adds:

"... and he who exchanges faith for infidelity, he has surely strayed
from the right way."

it should be noted that islam has never prevented people from
asking scientific or logical questions, as well as asking the prophet
(p.b.u.h.) to perfoem miracles in order to prove the divine rightfulness of
his prophecy, because the means of gaining understanding and faith are the
same. but there were some people who asked some futile questions and demanded
some irrational pretexts in order to shirk the invitation of the holy prophet
(p.b.u.h.).