This is a Brother Tonto and Cappa Cartoon. It looks like Cappa has given up "mice" for Lent. There is a story about St. Martin de Porres regarding this same problem. When the priory was overrun with mice, the prior turned to Martin for help. The prior knew that Martin loved all animals, including rodents, and when the prior told Martin to find a way to rid the priory of the vermin, or he, the prior was going to kill them all.
It is said that Martin called all the mice together, and explained the problem. Martin told the mice to stay out of the priory, and especially to stay out of sight of the prior. In return, Martin would feed them daily--in the barn. It worked like a miracle.