不做虧心事，不怕鬼敲門 [－－亏－－－－－－－门]

Jyutping bat1 zou6 kwai1 sam1 si6 , bat1 paa3 gwai2 haau1 mun4
Pinyin bù zuò kuī xīn shì , bù pà guǐ qiāo mén

Definitions (CC-CEDICT)
  1. he who never wrongs others does not fear the knock in the night; you can rest with a clear conscience