Yet in the rest of the universe, it is one of the rarest of the rare elements. We look out the windows in the morning and overnight it has formed on the grass. Some days, we look out the windows and it is falling from the sky. In the winter, it freezes and accumulates in drifts. So common, yet it is so vital to our survival, but on the moon or planets, finding water is nearly, if not, impossible.
Water has a high specific heat.
This means that the chemical reactions in the human body will be kept rather stable. If water had a lower specific heat, the water in our bodies would boil with the least amount of activity. If it was higher, we could not keep our body temperature at the 98 degrees needed to survive. We need water just as God created it or life would be impossible. Earth's surface was modulated by the ocean, and kept within certain limits, we would either be cooked to death or frozen to death.