Why is のこと used in the sentence below?

Or more specifically, what is the difference between V-ときです and V-ときのことです?

> むかし、むかし、桶屋で働く若者が桶にする竹を切っていた時 **のこと** です。
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2017-06-09T12:33:59.733
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2017-06-09T13:41:01.400
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question
grammar
What is the difference between Verb+ときです and Verb+ときのことです?
* V-ときです: It happened when he was sawing a bamboo trunk. 
  * V-ときのことです: It was the event that happened when he was sawing a bamboo trunk. 

The former one pays attention to the time, while the latter one pays attention
to the event.
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2017-06-09T13:12:50.940
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2017-06-09T13:12:50.940
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answer
> 桶にする竹を切っていた時

Would refer to the time he cut the bamboo.

> 桶にする竹を切っていた時のこと

Refers to the things (こと) that happened during the time he cut the bamboo.
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2017-06-09T13:13:46.063
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2017-06-09T13:13:46.063
10548
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answer
This is going to help a lot in answering your question: [What is the こと in
sentences such as
あなたのことが好きだ?](https://japanese.stackexchange.com/questions/2102).

The selected answer explains how こと or 事【こと】 can be used in a few
significantly different ways:

  * to encompass the things around an object/concept (i.e. "about"), like your sentence does --

> 時のこと (the event... / the thing(s) that happened when...)

  * to simply mean "thing"

  * > to add a layer of indirectness
CC BY-SA 3.0
2017-06-09T13:41:01.400
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2017-06-09T13:41:01.400
48225
answer