Silence is the true friend that never betrays. Confucius
Your representative owes you, not his industry only, but his judgment; and he betrays instead of serving you if he sacrifices it to your opinion. Edmund Burke
And oftentimes, to win us to our harm, The instruments of darkness tell us truths, Win us with honest trifles, to betrays In deepest consequence. William Shakespeare
The cheese betrays the milk. Finnish Proverb
If someone betrays you once, it is his fault. If he betrays you twice, it is your fault. American Proverb
A face that never laughs betrays an evil heart. Basque Proverb