Comment by alganet
> our culture has trained us to take rhyme less seriously
As I was reading this, I realized compositions with metric and rhyme are a good way of decreasing the chances of someone altering them.
I'm thinking about the times before the printing press. Times when people copied books by hand, sometimes altering stuff during the process. I imagine altering a composition that has strict form is much harder than altering free text. Can't just insert or remove words freely (metric would change), can't just exchange a word by some other unrelated word (rhyme would change). Someone wanting to modify such works would need to be more than copyists.
More than that, just as nowadays we can easily remember the lyrics of a famous song, the Greek remembered and recited parts of the Iliad and Odyssey. This is easier to do with poetry than with prose.