Translation of the verse 40 from Surah Yunus : Number of verses 109 - - page 213 - Part 11.
And of them there are some who believe therein, and of them there are some who believe not therein, and your Lord is All-Aware of the Mufsidun (evil-doers, liars, etc.).
And of them are those who believe in it, and of them are those who do not believe in it. And your Lord is most knowing of the corrupters
(10:40) Of those some will believe and others will not. Your Lord knows best the mischief-makers. *48
*48). The statement that 'Your Lord knows best the mischief-makers' underscores art important fact about unbelievers. Those unbelievers could certainly silence others into not carrying the discussion any further by openly admitting that they had failed to grasp the teaching of the Qur'an and hence it was not possible for them to sincerely believe in it. God, however, is well aware even of the things that are hidden, even those that are in the deepest recesses of their hearts and minds. He knows how each person has sealed his mind and heart against accepting any truth; how he has sought to immerse himself in heedlessness; how he has managed to suppress his conscience; how he has prevented the testimony of the truth from affecting his heart; how he has destroyed the innate capacity of his mind to accept the truth; how he has heard the call of the truth and has turned a deaf ear to it; and how, despite his ability to understand the Message of God, he has made no effort to do so. Such people cherish their biases and prejudices, their lusts and desires, their worldly advantages and the interests which can be procured only by supporting falsehood, much more than by accepting the truth. Such people can hardly be considered to have innocently succumbed to a 'mistake'. On the contrary, they are rank 'mischief-makers'.