expression
honey in the mouth, a sword in the belly
Proverb warning that sweet words can hide malicious intent; equivalent to 'a wolf in sheep's clothing' or 'fair words butter no parsnips'.
彼は口に蜜あり腹に剣ありというタイプだから、気をつけたほうがいい。
He's the type who has honey in his mouth but a sword in his belly, so you'd better be careful.
口に蜜あり腹に剣ありということわざを知っていますか。
Do you know the proverb 'honey in the mouth, a sword in the belly'?
A Japanese rendering of a classical Chinese proverb, likely from the Tang dynasty text '意林' (Yilin), which says '口有蜜腹有剣'. The expression was naturalized into Japanese using the classical literary form あり.