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destiny; fate; karma
二人の出会いは宿縁によるものだと感じた。
I felt that their meeting was brought about by fate.
宿縁に導かれて師弟の絆が結ばれた。
Guided by destiny, the bond of master and disciple was formed.
宿縁の深さを信じて修行に励んだ。
Believing in the depth of karmic ties, he devoted himself to training.