Midrash su Giudici 15:4

(Ib. 15, 4) And Samson went and caught three hundred foxes. Why did he choose foxes? Said Ibbai, the son of R. Agdi, in the name of R. Chiya b. Abba: "Samson said: 'Let the fox which has a habit to retract, come and mete out our punishment to the Philistines, who violated their oath.'" We are taught that R. Simon, the pious, said: "The distance between both shoulders of Samson was sixty cubits, as it is said (Ib. 16, 3) And Samson laid till midnight but he arose at midnight and took hold of the doors of the city gate and two-door-posts and took them away with the bolt, and put them upon the shoulders. And we are taught in a Baraitha that the doors of Gazzah were not less than sixty cubits in length."