Exodus 4:6-7

And Jehovah said furthermore unto him, Put now thy hand into thy bosom. And he put his hand into his bosom: and when he took it out, behold, his hand was leprous, as white as snow. And he said, Put thy hand into thy bosom again. (And he put his hand into his bosom again; and when he took it out of his bosom, behold, it was turned again as his other flesh.)