Thirty pieces of silver
The money Judas Iscariot received for betraying Jesus to the authorities. Helater threw the money into the Temple of Jerusalem, and the chief priestsbought the “potter's field” with it, to be used as a cemetery for foreigners.
Meaning of this idiom:
This money is referred to as “blood money” — money received for thelife of another human being.
“Thirty pieces of silver” is also used proverbially to refer to anything paidor given for a treacherous act.
有一个称为加略人犹大的，去见祭司长说， 我把他交给你们，你们愿意给我多少钱。他们就给了他三十块钱。 从那时候，他就找机会，要把耶稣交给他们。
后来，卖耶稣的犹大，看见耶稣已经定了罪，就后悔，把那三十块钱，拿回来给祭司长和长老说，我卖了无辜之人的血，是有罪了。他们说，那与我们有什么相干？你自己承当吧。
犹大就把那银钱丢在殿里，出去吊死了。祭长拾起银钱来说，这是血价，不可放在库里。他们商议，就用那银钱买了窑户的一块田，为要埋葬外乡人。
这个成语的意思是：
血钱 - 出卖别人性命所得到的钱；
背信弃义