The past has been destroyed, there is no new becoming.
How does Vipassana help us to stop tying new knots and to open up the old ones, eradicating all the accumulations of the past?
The Teaching says that first, a meditator should sit correctly nisinno hoti pallankam abhujitva ujum kayam panidhaya cross-legged and erect.
Then he sits with adhitthana (very strong determination), no movement of the body of any kind.
Now at the grossest physical level, all the bodily and vocal actions are suspended so there can be no new physical kamma (kayika-kamma) or vocal kamma (vacika-kamma).
A Vipassana meditator soon realizes the difference between apparent and actual truth. By simply observing objectively and equanimously feeling the sensations in one's own body in a proper way, one can easily reach a stage where even the most solid parts of the body are experienced as they really are-nothing but oscillations and vibrations of subatomic particles (kalapa). What appears solid, hard and impenetrable at the gross level is actually nothing but wavelets at the subtlest, ultimate level.
With this awareness, one can observe and realize that the entire pancakkhandha, the five aggregates, are nothing but vibrations, arising and passing away. The entire phenomenon of mind and matter has this continuously ephemeral nature.