Modern Science has discovered that in the places where two different seas meet, there is a barrier between them. This barrier divides the two seas so that each sea has its own temperature, salinity, and density. For example, Mediterranean sea water is warm, saline, and less dense, compared to Atlantic ocean water. When Mediterranean sea water enters the Atlantic over the Gibraltar sill, it moves several hundred kilometers into the Atlantic at a depth of about 1000 meters with its own warm, saline, and less dense characteristics. The Mediterranean water stabilizes at this depth. Although there are large waves, strong currents, and tides in these seas, they do not mix or transgress this barrier.
The Holy Quran mentioned that there is a barrier between two seas that meet and that they do not transgress. Which is a true statement.
Once again Muhammad has knowledge of something that would have seemed to be impossible for him to have know that. Especially as he can neither read nor writeat that time. It is virtually impossible and would be seen as a miracle maybe that he knew all this information especially at that time.
The true meaning of Islam is submission and the commands of Allah. You must completely believe in Allah and only Allah aswell as obeying his commands.
It is a well known fact that everything in this universe follows certain rules, so when Allah created the universe he created gravity aswell as the stars and the sun, anything living non-living etc. will follow Allahs rule which he has given to each thing. Even man himself, when you consider his physical construction, and biological compounds, his need for water and nutrition, heat, air, light, rest, or sleep you would find him submitting to a law under which he has no choice, just like other creatures.
This inclusive law to which everything submits, is the work of Allah, the Majestic King, to Whom belong the creation and the authority. Both of the upper and the lower worlds submit willingly to the Creator, the Capable King.
Due to the fact that the linguistic meaning of Islam is submission, and adherence without objection, Islam, from this point of view, is the faith of the universe. Man in this sense, does not differ from the other creatures. Since Allah, is the Creator and the Provider, He has given man the freedom of choice, and has shown him both, the path of guidance, and the path of deviation through the Messenger that He sent to mankind throughout the ages; the last of whom is Muhammad, peace be upon them all. Therefore, he who chooses the path of guidance of his own free will, and fulfills the duties with which he is charged, and refrains from the prohibition, then he becomes the legitimate Muslim.