彼は晩年、一向に念仏を唱えて過ごした。
In his later years he spent his days single-mindedly chanting the nembutsu.
僧は一向に仏道の修行に励んだ。
The monk devoted himself wholeheartedly to Buddhist practice.
一向に学問に打ち込む日々が続いた。
Day after day he threw himself single-mindedly into his studies.