The Scarlet Letter

This is a story of a woman who fell in love with a man who wasn't her husband. She was married, sure, and all signs say she did love and respect her husband, but... for some reason, maybe because... Because Nathaniel Hawthorne was for free love, 1850, when he wrote this book.
...

“She assured them, too, of her firm belief, that, at some brighter period, when the world should have grown ripe for it, in Heaven's own time, a new truth would be revealed, in order to establish the whole relation between man and woman on a surer ground of mutual happiness.”