Classic Reads Blog Hop

What, for you, makes a book a classic?
As soon as I read what this blog hop was about, I knew I had to join! Not only because of the wonderful blog hop hosts who are great online friends of mine, but because of my great-great-great grandfather's Hispanic Literary Classic, Lejos Del Nido. 
The question for this blog hop is what, for you, makes a book a classic? To me, for a book to become a classic, it has to withstand the passage of time. There are many contemporary novels that have potential to become classics but in my opinion, only time will tell.
Thanks so much to my good friends and hosts of the blog hop! Check out their books below: