一把钥匙，开一把锁 (一把鑰匙，開一把鎖) yī bǎ yào shi, kāi yì bǎ suǒ

yī bǎ yào shi, kāi yì bǎ suǒ phrase each key opens up a lock
Domain: Buddhism 佛教 , Subdomain: Fo Guang Shan
Notes: (Glossary of Humanistic Buddhism)