In every age there were people turning down the truth and turning down the callers of truth (the Messengers and their righteous followers). Allah Taala announces explicitly in the Qur’an in several verses that whatever the non-believers, hypocrites and atheists proclaim, every Promise of Allah is definite; truth will certainly be unveiled (what Allah has promised is to materialize) and every human will definitely be recompensed for his deed. One example of Allah Taala’s explicit message has been mentioned below (Every Believer should ponder on the Verses of Qur’an):
Allah Taala says in Sura Fatir (Meaning):
Consoling the Caller of Truth, His Prophet, Allah Taala informs (meaning):
And if they reject you,( it is not something new, because) many messengers have been rejected before you. And to Allah all matters are to be returned. 
And right after that Allah warns addressing all people of the world (not the believers only); here the two big deceptions – the worldly life and satan have been mentioned (meaning):
O mankind, Allah’s promise is definitely true, therefore, the worldly life must not deceive you, nor should you be deceived about Allah by the big deceiver (Satan).
Allah Taala emphatically specifies who the devil or satan is, what is his mission (meaning):
Surely Satan (shaytan)is an enemy for you. So, take him as an enemy. He invites his group only to cause them to be among the people of blazing fire.
He also mentions the extremely negative outcome of disbelievers; on the other hand, He mentions the reward for the believers (meaning):
Those who disbelieve will have a severe punishment; and those who believe and do righteous deeds will have forgiveness and a great reward. 
Allah Taala clarifies the stance of evildoers and also, it is because of their deeds they have been left astray (meaning):
Is it, then, that the one whose evil deed has been made attractive to him so much that he deems it to be good (will be held equal to him who differentiates between right and wrong) ? The fact, therefore, is that Allah lets go astray whomsoever He wills , and leads to the right path whomsoever He wills. So, let not your soul collapse in grief for them. Surely Allah fully knows what they are doing. *
* This does not mean Allah Taala forces to become people astray. Rather, it means, one who defiantly moves astray from the righteous path is deprived of the righteous path. Refer to the commentary of Sura Baqara’s these verses (click) for clarification please.