78. " and verily among them is a group who twist their tongues with the book
that you may suppose it to be from the book, but it is not from the
book; and they say: `it is from allah', while it is not
from allah; and they speak falsehood against allah and they know (it)."

occasion of revelation:
this verse was also revealed about a group of the jewish scholars
who used to write with their own hands some things against what was found
in the torah about the characteristics of the messenger of islam (p.b.u.h.)
and said that it was from the lord. they perverted the facts of the torah
with their speech.

commentary:
in this verse, again, the words are about some other wrong actions of
a group of scholars of the people of the book. it says:

" and verily among them is a group who twist their tongues with
the book that you may suppose it to be from the book,
but it is not from the book;

they did not suffice to that action either, but they explicitly said that
it was from the side of the lord:

" ... and they say: `it is from allah', while it is not from allah;... "

then, the qur'an emphasizes that this action was not done because
of their mistake, but they knowingly told a lie about allah.

"... and they speak falsehood against allah and they know (it)."

by the way, from this verse and its previous verses, the great danger
of the deluded scholars for a community and a nation is made clear.