There’s so much I want to say but I don’t even know where to start, my words won't do the novel justice.
So much sadness, so much beauty. 
With it being a long novel, by the end I was so invested in the characters, I was sad when it came to an end. I particularly loved the conversations between Samuel and Lee & Samuel and Lee and Adam, they were so compelling and interesting. And the character development of them all, for better and for worse, was perfect.
I also think the links to Cain and Abel & Adam and Eve were so well done, at times I was sat in awe at how their lives slowly intertwined and helplessly fell into these stories that we know.
This was the first novel I have read of Steinbecks and I must say, I don't think it'll get any better than this.