Most surely there is a party amongst those who distort the Book with their tongue that you may consider it to be (a part) of the Book, and they say, It is from Allah, while it is not from Allah, and they tell a lie against Allah whilst they know.

And certainly We know that they say: Only a mortal teaches him. The tongue of him whom they reproach is barbarous, and this is clear Arabic tongue.

When you received it with your tongues and spoke with your mouths what you had no knowledge of, and you deemed it an easy matter while with Allah it was grievous.