In the middle ages, kanjin was a source of funds for public works ranging from the construction and maintenance of bridges and roads to the building and repair of kanji (state-sponsored temples) (including temple bells, Buddhist statues and handwritten sutra), although the Chotei (Imperial Court) or kokuga (provincial government) should have done so.
中世においては、橋や道路の修理・整備から官寺（鐘や仏像、写経をふくむ）の建設や修造など、本来は朝廷（国家）や国衙（地方行政機関）がおこなうべき公共事業も、勧進によってなされた。