What is the central idea called in fiction

When first i engaged in this work, i resolved to leave neither words nor things unexamined, and myself with a prospect of the hours which i should revel away in feasts of literature . . –preface to a dictionary of the english language, samuel johnson what is the connotation of the word revel in this passage?

"the beginning of the massai" which excerpt best justifies this conclusion

Which of the following is an element of plot