Tsuihou Seijo no Doronko Nouen Seikatsu: Itsunomanika Ringoku wo Sukutte Shimaimashita

Saint Flafre has been in an underground prison for many years, where her holy powers have been exploited and she has been treated cruelly, eventually losing them. The king then decides she is of no use and banishes her from the country, bearing the insults of the people. Abandoned in the wilderness, she loses consciousness and waits for death, but is saved just in the nick of time by King Forst of the neighboring country. Upon waking up, Flafre is treated well in the neighboring country and gradually regains her holy powers... This is the story of the innocent Saint Flafre, who unconsciously saves her country while enjoying farm work covered in mud.

(Source: Futabasha, translated)