The devil represents the evils of the world. Wax and Wane refers to the moon at its brightest and darkest (to the point of not being visible).
The evils of the world are consistant ("The devil might steady"), but we cycle back and forth from our best to our worst, worst to best, and so on. ("We wax and wane").
I think it's pretty simple, really.
The devil represents the evils of the world. Wax and Wane refers to the moon at its brightest and darkest (to the point of not being visible).
The evils of the world are consistant ("The devil might steady"), but we cycle back and forth from our best to our worst, worst to best, and so on. ("We wax and wane").