Letters from the earth by Mark Twain. An excerpt:
"Thou shalt not commit adultery" is a command which makes no distinction between the following persons. They are all required to obey it:
Children at birth.
Children in the cradle.
Youths and maidens.
Men and women of 40.
The command does not distribute its burden equally, and cannot.
It is not hard upon the three sets of children.
It is hard -- harder -- still harder upon the next three sets -- cruelly hard.
It is blessedly softened to the next three sets.
It has now done all the damage it can, and might as well be put out of commission. Yet with comical imbecility it is continued, and the four remaining estates are put under its crushing ban. Poor old wrecks, they couldn't disobey if they tried. And think -- because they holily refrain from adulterating each other, they get praise for it! Which is nonsense; for even the Bible knows enough to know that if the oldest veteran there could get his lost heyday back again for an hour he would cast that commandment to the winds and ruin the first woman he came across, even though she were an entire stranger.