protected function forbidAbilities(array $ids, Model $authority = null)
    {
        $ids = array_diff($ids, $this->getAssociatedAbilityIds($authority, $ids, true));

        if (is_null($authority)) {
            $this->forbidAbilitiesToEveryone($ids);
        } else {
            $this->forbidAbilitiesToAuthority($ids, $authority);
        }
    }