Can someone explain sura 51:56?

sura 51:56 i did not create men or jinns except that they worship allah.;;; sura 14:4 allah leads astray whomever he will and guides whomever he wills. nay! to those who believenot, pretense seem pleasing, but they are kept back from the path and those allah leads astray, none can guide; sura35:8 thus doth allah leave astray whom he will, and guides whomever he wills. so let not thy soul sighing after them; sura 74:31 if it had been his will, he could indeed have guided you all; thus doth allah leave to stray whom he pleaseth and guide whom he pleaseth;;;;;;;;;;;;;;;; so why would a god lead people astray and seal thier hearts from the truth, seal their ears and eyes from [islam] then sent them to hell for something he did to them?