for when they come unto you they say we do believe whereas in fact they come with the resolve to deny the truth and depart in the same state. but god is fully aware of all that they would conceal.
وإذا جاءوكم قالوا آمنا وقد دخلوا بالكفر وهم قد خرجوا به والله أعلم بما كانوا يكتمون