myself, oneself

to take a oath to oneself

taking a oath to oneself

[one]self

(archaic, Shinto, Japanese mythology) an "oath", a ritual in which whether something is true or false, right or wrong, good or evil, etc. is judged based on whether the stated outcome of an act comes true as expected

vow / swear / pledge

oneself / first-person pronoun: I, me (often shows the speaker's lower position in a hierarchy than the addressee) / (Kansai) you

success / success in life, achievement in the world

succeed / be successful in life

he / distal demonstrative, something far off removed from both speaker and listener: that / boyfriend