嘢可以亂食，說話唔可以亂講 [－－－乱－－说话－－－乱讲]

Jyutping je5 ho2 ji5 lyun6 sik6, syut3 waa6 m4 ho2 ji5 lyun6 gong2
Pinyin yě kě3yi luàn shí2 shuō1hua wú kě yǐ luǎn4jiang

Definitions (CC-CANTO)
  1. one must watch what comes out of their mouth (what they say) more so than what they put into their mouth (what they eat) [colloquial]