They begin to change the moment they are created, and from them are born innumerable forms, which in turn change and give rise to newer forms, and so on and on, in infinite succession.
Nothing is permanent in the world of forms, and yet the great Reality is unchangeable.

Forms are but appearances--they come, they go, but the Reality is eternal and unchangeable.
The atoms of the human body are in constant vibration.

Unceasing changes are occurring.

In a few months there is almost a complete change in the matter composing the body, and scarcely a single atom now composing your body will be found in It a few months hence.
Vibration, constant vibration.

Change, constant change.
In all vibration is to be found a certain rhythm.