وَإِنَّمَا التَّعَدُّدُ وَالتَّفَاوُتُ فِي النَّظْمِ الْمَقْرُوءِ الْمَسْمُوعِ
Multiplicity and variation occur in the arrangement that is recited and heard.
Revealed books can differ in words, arrangement, audience and form of expression. This difference belongs to recited and heard discourse; it does not overturn the asserted unity of the eternal divine attribute.
A command and a promise are different types of address. Their distinctions do not imply multiple divine persons or separate, independently eternal speech-beings.