Imam Khomeini thorugh his theological works explains the matter as following:
Moreover, He has sent His messengers and prophets and His Books as well to show us which path is right and which one is wrong, which path leads us to Heaven or Hell. He fulfills all our needs in this world and the Hereafter, without having any need of our adoration.
Observance of His commands, or transgressing them does not make any difference to Him, it is for the sake of our own benefit that He has enjoined good and forbidden indecencies.
While remembering all these and various other favors, whose reckoning is beyond the powers of human beings, do we not see that respecting and obeying such a Benefactor is essential for us, or does our reason approve of the acts of violating His commands?
This is an evident fact that we respect great people and those older in age.
This is also true that people respect the wealthy and powerful persons, and rulers and kings, since they are recognized as great.
Can their greatness be matched with the grandeur and magnificence of that King of kings, in Whose kingdom this world of us is merely a particle of dust.
He is the Creator and King of this vast cosmos, whose infiniteness cannot be measured or even conceived by human intellect.