〜ばこそ

Meaning

Expresses an emphasized cause or reason, "precisely because that is the reason." A formal expression highlighting that very reason and no other. Often followed by 「のだ」.

Examples

君のことを思えばこそ、あえて厳しく言うのだ。 It is precisely because I care about you that I am being harsh.
健康であればこそ、思い切り仕事に打ち込める。 It is precisely because one is healthy that one can throw oneself into work.
努力があればこそ、今日の成功があるのだ。 It is precisely because of the effort that today's success exists.