The context is that of two equally holy men giving a sermon on aspects of divinity. Both very old, yet one vigorous, the other fragile. I am tempted to see in these two figures metaphors for personality and essence. I seem to remember that, from the author's perspective, the problem is that personality tends to develop at the expense of essence, being. One is over developed, the other atrophied. Both knowledge and being are pictured as holy men by G.
One is grounded in memory and can use words, thought eloquently. It can communicate but does'nt penetrate the essence of things and often mistakes the word for the thing. It is entertaining, as words, concepts and images tend to be but doesn't leave a deep imprint on the listener. It is of the mind and and only speaks to the mind.
The other doesn't define, judge and conclude but observes and notices the discreet, the subtle. He can penetrate the essence of things and can see, sense the reality beyond the word, the mask, the persona. He does'nt seek to entertain but seeks to touch the deeper and finer fabric in the mind-heart of the listener.
Given the right space being can inform, educate personality and use it. Then knowledge and understanding can move together with some harmony.