The practice of a Zen monk giving his portrait (or called Chinzo) with gasan to his disciple after he had completed ascetic training was introduced together with the Zen sect after the Kamakura period.
禅僧が修行を終えた弟子に自分の肖像画（頂相）に画讃をいれて、弟子に与える習慣が、鎌倉時代以降、禅宗とともに導入された。