that every psychic activity carries its somatic repercussion and inversely that attitudes and movements of the body may favour, even provoke, mental states. The body, perceptibly or imper¬ceptibly, takes part in every movement of the soul—whether of feeling, of abstract thought, of volition, or even of transcendent experience.
I have been reading a catchesis for new Christians written by Clement of Alexandria in about 190 AD. (Christ the Educator or Pedagogue) It's amazing how things never change and how relevant what he has to say if for today. He address this issue, not in terms of hesychastic prayer, which is probably above all of our heads anyway, but in the practical day to day issues of self-restraint and frugality in eating, speech, dress, possessions, etc. Most of what he addresses would simply be seen as "good manners" and ignored as nothing particularly spiritual and basically unimportant by a lot of Christians today, but for Clement these issues, for the new Christian coming out of a pagan culture, were precisely the first step on our road to deification. And I think it has to do with the recognition of what is quoted above as far as the relationship of body and soul go.
He starts out his chapters on practical living with a statement about the goal "Now whenever a man is drawn by reason (logos) away from external things and even from any further concern for his body to the realm of understanding and aquires clear insight into the natural atributes of man, he will understand that he is not to be eager about external things, but to purify that which is proper to man, the eye of his soul, and to sanctify even his body."
How then do we do this? Well he doesn't start with prayer he starts with "Other men live that they may eat, just like unreasoning beasts; for them life is the belly. But as for us, our Educator has given the command that we eat only to live. ... Our food should be plain and ungarnished, in keeping with the truth, suitable to children who are plain and unpretentious, adapted to maintaining life, not self-indulgence."
He goes on to address in a very long and detailed and sometimes quite funny manner the necessity for simplicity, frugality balance and self-control in our eating. The next chapter is about the moderate use of drink. He covers the need for decorous behavior, and restraint and propriety in speech. He covers listening to chaste music rather then something sensuous or that excites the passions. He goes on to talk about self-control in social situations - neither guffawing nor giggling, but having "good humor that is self-contained." "It is well that even the smile be kept under the influence of the Educator." He even addresses how to sneeze politely. Throughout his instructions one sees then the ongoing themes of good will toward our neighbor and self-restraint over all thing in our bodily actions as being the beginning of the Christian life.
These things in fact became so ingrained in Christian culture that we now hardly think of them in their Christian context, for us they are merely empty manners from the "old days". But here in Clement we see how they got their beginning and why they were considered important.
Our culture is in the process of rejecting everything that Christianity had once built into it as irrelevant. And now "being real" with our friends or family means, not self-restraint, hospitality and good will, but rather acting out on whatever we happen to think or feel. As this happens, I think that this whole understanding that Clement is teaching really needs to be regained.
If we have not first developed these bodily and mental "postures" that ought to be proper to even to every Christian laymen, why are we discussing postures appropriate to higher levels of prayer?
Quotes are from Christ the Educator, by Clement of Alexandria, CUA press, Father of the Church series vol 23 the link is to the google book online. His humor is very engaging. Quotes are from bk 2, ch 1 (starts pg 93)