what is voice on writing

voice in Moods is an important factor because the way he narrate his thoughts is through what his thinking. he doesn't write just to fulfill a page but to reflect what he is thinking, sometimes is very hard for us to say things but writing is a way of telling them without saying it loud. in most of the fragments he writes based them on his experiences, like the holocaust which he mention very little,  that makes us understand that it was hard for him to talk about it in details but the way he writes makes us understand that it was a hard time an somehow it has a lot of impact on his life, just like in his writing.