Informing about the past nations and the torment and disciplinary lessons that they suffered because of opposing the Messengers and denying the truth. Allah says;
(Has not the news reached you of those who disbelieved aforetime) meaning, information about them and what happened to them,
(And so they tasted the evil result of their disbelief.) They tasted the evil consequences of their denial and sinful actions. And it refers to the punishment and humiliation they received in the life of the world,
(and theirs will be a painful torment.) in the Hereafter, added to the torment they received in this life. Allah explained why;
(That was because there came to them their Messengers with Bayyinat,) supporting arguments, evidence, and clear proofs,
(but they said:"Shall mere men guide us") They discounted and dismissed the possibility that the Message would be sent to a human and that their guidance would come by the hands of a man like themselves,
(So they disbelieved and turned away.) they denied the truth and turned away from abiding by it,
(But Allah was not in need.) of them,
(And Allah is not need, Worthy of all praise.)