Why did the handmaid tell the story of the ceremony at the same time she tells the story of Moira’s escape?

I need the story

Explanation:

gimme

The most details can be found in the following sentence:
The apartment shuddered under the onslaught of the howling wind.

The details in this sentence were:
-how was the wind? it was howling
-why did the apparement shudder? under the onslaught of the wind!