It is important in terms of Dhamma that there is an image of the body that can be formed in the mind and that is independent of the five senses and of sensations of pleasure and pain. This means that this image can remain in its pure form when the mind is withdrawn from the senses in samādhi. This is the way that an image is held and examined in a place where the mind is pure. This is the way we see the truth of the body and can let go of attachment to it and consequently attachment to all the rest. This is the end of inner suffering.
This inner image is then compared with the outer image of the body, our own and other people's bodies as seen from the outside. In this way we transform this image as well, allowing us to let go of desire related to the bodies of others as well as our own. This is freedom from suffering, inner and outer.
This body image, which is thus at the very heart of the quest for liberation, is formed through a combination of awareness of the movement, posture and elements of the body. Meditation experience (and also evidence from neuroscience) shows us that the mind has sources of the relevant information on these aspects of the body which do not involve the five senses or feelings of pleasure or pain. There are the sensations of the hardness of bones or the softness of the belly that are neutral, neither pleasant nor painful and that through awareness form an image over time of a part of the body in the mind. Then there are neural receptors in our joints that tell us the position of our limbs, giving us information on movement and posture. There are sensors of heat and cold and a sense of the position of the body in relation to gravity.
All this information can form a neutral image in the mind of the real body, in the same place as the real thing, which is not imagined but arises spontaneously. We then find that we can examine and manipulate this image and that this takes our samādhi deeper and deeper until we let go of the body completely.
This is the end of all stress. This can become established as a natural state and a permanent end to stress. Also, if we believe those who have realised such a state, it is clear to them that this is also the end of the cycle of rebirth and therefore an end to all future suffering.