How did mankind come under Satan’s rival sovereignty? Basically, Satan implied that mankind would be happier following a path of independence from God.
مِنْ حَيْثُ ٱلْأَسَاسُ ،‏ لَمَّحَ ٱلشَّيْطَانُ أَنَّ ٱلْبَشَرَ يَكُونُونَ أَسْعَدَ حَالًا بِٱلِٱسْتِقْلَالِ عَنِ ٱللهِ .‏