To develop Sanchin the three conflicts must first be recognized, harmonized and finally refined. These conflicts are those of the undisciplined Mind, Body and Breath.

The Mind, it is the discipline of concentration that clears the the countless random thoughts
that constantly distract us. Therefore when studying Sanchin we refrain from internal verbalizing and concentrate on experiencing the feelings instead. This is the state of mushin.

The Body, constant repetition combined with self awareness corrects poor body alignment and brings control to erratic body mechanics. It restores the bodies natural balance and posture. Natural strength is developed in favour of excessive tension or relaxation

The Breath, abdominal breathing replaces restrictive thoracic (chest) contraction and expansion that manifests as shallow chest breathing. This enables the tension in the upper body to be released from the chest and is pushed down into lower abdomen (hara).

Each conflict can be seen as a dull unpolished stone, that through the practise of Sanchin each stone abrades the rough surface of the other, until three jewels emerge.

The polishing of the 'three conflicts', requires intention or Ki. Concentrate without distraction on natural movement and posture, combined with co-ordinated abdominal breathing. This may take many years but with patience and perseverance will come the rewards.

The cutting mind is the calm clear mind that perceives and acts with out the incessant chatter of the internal dialogue. The starting point of Zen; the uncluttered mind that allows direct experience and reaction at an instinctive level. To empathize with the enemy enables their movements to be intuined so as to cut them down without hesitation at precisely the right moment.

The body of armour is commonly referred to a 'Iron Shirt', and is the effect whereby the body is able to absorb and withstand blows. This is done by developing and utilizing the muscles, bones and tendon throughout the whole body to absorb and dissipate the force, much like a giant shock absorber.

The explosive power is generated by using the whole body and then channelling and directing it into the opponent. In the initial stages a single shock wave is produced, hence the intent of 'the single killing blow'. In the higher levels this manifests as a series of continuos waves or vibrations. The source of this power is the from the hara or lower abdomen combined with contractions of the diaphragm (i.e. breathing). Crane boxing refers to this as 'shaking' or 'trembling', in the Chinese internal arts this explosive energy is called 'Fa Jing'.

References:

Five Ancestor Fist Kung-Fu by Alexander L.Co, printed by Charles E.Tuttle 1997 ISBN 0-8048-3153-X