Jesus and walking on water

Many people try to explain miracles wrought by Jesus through science. Some assumptions that issued: to walk on water Jesus had to cancel gravity. But this would have meant to had antigravity device, which was impossible at that time when science was almost nonexistent.
And even today, with a quite advanced science, we could do a device capable of something, that does not mean anything. There are miracles that can not be explained by science. Nor is worth try explaining them.