had allah willed he would have made you all one nation but he sends astray whomever he wills and guides whomever he wills and you will certainly be questioned regarding your deeds.
ولو شاء الله لجعلكم أمة واحدة ولكن يضل من يشاء ويهدي من يشاء ولتسألن عما كنتم تعملون