This works on the same principle as a moving boat. As the boat moves with speed, a void is created behind it. It is this void that helps the boat to move ahead. Water from all sides rushes to fill the void; this pushes the boat forward. This is the trick that works all along. Should the water behave differently, the boat will not move.
So if a car is made to run at a particular speed, a four-foot thick layer of air can be made underneath for it to function as a road. In fact, there is no need to make it really – it will be formed automatically as the car moves at high speed. Then there won’t be any need for wheels; the car will simply slide along. Then nothing else will matter – only air will be needed, that’s all.
Hatha Yoga has discovered many techniques which give the body a special discipline. Giving such a discipline makes the difference. That’s why a hatha yogi never dies young. A normal raja yogi dies at a young age like Vivekananda or Shankaracharya, but not a hatha yogi. And the reason is that the hatha yogi gives a total discipline to his body before such a happening can take place. In order to prepare his body to withstand any unnatural situation, he performs many unnatural practices.
For example, when it is hot outside he will cover himself with a blanket. Sufi mystics wrap a blanket around themselves. The word suf means wool. One who always covers himself with a woolen wraparound is known as a Sufi. There is no other meaning of the word sufi.
All Sufi fakirs in the Arab world, where the sun is burning hot, move around in blankets. In that scorching heat they wrap themselves in a woolen blanket. They create a very unnatural situation. As it is, the sun is sizzling hot, there is no greenery anywhere around, and a man is sitting there wrapped up in a blanket. He is making his body able to withstand unnatural conditions. In Tibet a lama sits naked on the snow, and you will be shocked to see perspiration running down his body. This lama is working on his body to perspire even under the falling snow. His effort is very unnatural.
There are many such ways of preparing the body. If the body has been made to pass through these preparations, it becomes fit to withstand any unnatural happening. Then no harm is caused to the body. But ordinarily these preparations take years. Consequently, the discipline of Raja Yoga finds it useless to spend so many years in preparation just to live a little longer. Hatha Yoga requires years of preparation. Twenty or thirty years are minimum – thirty years are needed at least. If a man begins at the age of fifteen, he would be fifty by the time he is fully prepared.
Hence, the discipline of Raja Yoga decided not to be so much concerned about the body. If such a state does occur and the body dies, then so be it. What is the need for saving it? So these preparations were abandoned.