How does flash backs in paragraph 46-54 create tension

The second chapter is a flashback to the staff meeting the previous week explaining how he got the job, and how each of the female teachers initially reacted to the news.

Explanation:

faithful servants eumaeus and philaetius:

his ragged vest then drawn aside disclosed the sign conspicuous, and the scar exposed: eager they view'd, with joy they stood amazed with tearful eyes o'er all their master gazed:

these servants know ulysses by the scar he got when he was a child - so when he showed them the mark, they immediately knew this is truly their master and they hugged him, finally starting to believe his words.

i think the literacy device is "it's frozen head"