The size of earth in the visible universe is like a drop of water in the entire ocean, of all the oceans in the world. Or like a sand grain in the seashore, of all the seashores of the world. Would the creator of such a vast universe be bothered if tiny humans living on a tiny planet worship Him as the only God and follow Muhammad or not? A journey by an airplane gives an indication as to how insignificant we are even on this earth. Looking down from an airplane, humans seem less than ants. Imagine ourselves as the creator of all the sand particles on the seashore of all the seashores of the world. Would we be so concerned that tiny creatures living on one tiny particle somewhere unknown follow us and if they don't worship us, would we burn them in Hell? Or would we be so concerned about tiny viruses living on a drop of water somewhere deep down in the Pacific Ocean? Imagine one such small creature who lives in a drop of water somewhere down the Pacific Ocean telling others that he is the Messenger of the Creator of all oceans i.e. us and if other viruses (which are so tiny that they are invisible) do not follow him, we will roast them in Hell forever. How ridiculous would it sound?
A well-known scholar and perhaps the most knowledgeable person on Islam in the world today, Ali Sina, has given an apt analogy. Imagine if there is an ant colony somewhere in our garden. Would we burn ants in fire and torture them if they don't worship us as the only Savior? Our garden and ants are still very significant, as compared to humans and the Universe. Our Milky Way galaxy is utterly insignificant in it. Then our solar system is an invisible speck inside this galaxy and then there is Earth. Even the sun, which we see everyday, is some 15 crore kilometers away from the earth, i.e. 150 million kilometers and it takes light a good 8 minutes to reach the earth from the sun. What is our significance in this universe? Nothing! Would the maker of such a vast universe be offended if we humans don’t worship him? It is utterly foolish to say such thing. The Hubble Space Telescope has detected galaxies that are 46 billion light years away from each direction of the Earth. That is an expanse of 92 billion light years from one side of the observable universe to the other side. The observable universe, which is 92 billion light years wide is not all the universe. The complete universe is much, much bigger. According to some calculation, the whole universe would have grown to some 10,000,000,000,000,000,000,000,000 times the size of the observable universe. That is 10 followed by 24 zeros. Put in another way, the complete universe is to the observable universe, as the observable universe is to an atom.
Now, let us assume that the Creator (Assuming God exists) of this vast universe does indeed want all humans to worship Him as the only God and follow his only true religion. Surely He can do so in better ways. He can create mankind in a manner whereby everyone born with belief suited to Him. He can alter human brain in a manner whereby everyone will naturally worship Him as the only God and follow His last Messenger. Or He can show Himself to humanity, or at least send His angels to show them to humanity. This is not to state that God does not exist. God may well exist, and may have reasons for not showing Himself to mankind. But Islam is certainly not true.