There are (at least) three threads on this forum asking how to pause the game:
http://forums.demigodthegame.com/348845
http://forums.demigodthegame.com/347173
http://forums.demigodthegame.com/348715
I myself had to look up one of those threads to find out how to pause.
Why is the pause button not enabled by default during singleplayer?
It seems very counter intuitive.