Stubbornness and persistence

They solemnly swear by God: "If a sign comes to us we shall certainly believe in it." Tell them: "The signs are with God." Yet for all you know they will not believe if the signs came to them.

We shall turn their hearts and their eyes, for they did not believe them at the very first, and leave them to wander perplexed in bewilderment.

Even if We send down the angels to them, and the dead should speak to them, and We gather all things before their eyes, they will not believe, unless God should will, for most of them are ignorant.