“悖入悖出”常见的英文表达可以是 “Ill-gotten gains, ill-spent” 或 “What is gained dishonestly will be lost in the same way” 。
“悖入悖出”意思是以不正当的手段获得的财物，也会被别人以不正当的手段拿去；胡乱弄来的钱又胡乱花掉。上述英文表达都较好地传达了这一成语的核心含义。例如：
He always gets rich by illegal means, but it's just a case of ill-gotten gains, ill-spent. （他总是通过非法手段致富，但这就是悖入悖出的典型例子。）
As the saying goes, what is gained dishonestly will be lost in the same way. Don't try to get rich overnight by illegal means. （俗话说，悖入悖出。不要试图通过非法手段一夜暴富。）