Until pratyahara we are in what is called the bahiranga sadhana… gross definition of sadhana is the practice that we are doing, bahiranga means external… all the steps we took until this point are related to the external reality, yamas and niyamas are about we interact with the world at a behavioural level, asanas and pranayama are affecting our movements and breathing and will modify the physical interaction with the world.
All together the first 4 limbs will improve many aspects of our life at a physically external level… and this improvement will definitely start reflecting on our mind, it will start relaxing and coming a little more under our conscious control… or, at least, it will show us that it can be tamed!!!
Pratyahara is the crucial passageway, from the external work you’ll move to working inside yourself, the step here is about withdrawing your senses inside!
What does this mean?
Imagine to be willing to sleep in a room with a big analogic clock loudly ticking, imagine that you can’t sleep because of the sound of the clock really banging in your mind every second!
So there is you, there is an external distraction (the ticking sound), there is your will (to sleep), there is a sensory organ (the ear that is acquiring the external sound), there is a sense (the hear), there is your mind (that doesn’t agree with your will to sleep and keeps listening to the clock), there is your reaction (it’s 3 in the night, 6.30 wake up for some important job reason, you still couldn’t sleep one single second but keep hearing every single second… any feelings???)
Reading a book at the beach and relax??? Good luck my friend!!!