According to the text (which the above mentioned book has translated from the German for me), the bagpiper confesses to having liked women "too much" (if there is such a thing). He tells others like him not to do the same or they will find that women become "thorns in their eyes". As punishment for his actions he must ride his horse backwards (a medieval symbol of shame) and he goes on to advise to any man that if "their wives answer them back, they should beat them soundly or throw them to the ground (well, not every image can be politically, morally or just plain old correct).
At this point I can't even go on as the 16th century mindset is rather ludicrous and pretty perturbing. It is a cool picture none-the-less.