The phrase “itching palm” means: A wistful desire for money; a hankering for gain; avariciousness; readiness to receive a bribe.
Other bodily parts were metaphorically said to itch, even before Shakespeare’s time, such as an “itching tongue,” a craving to repeat gossip; an “itching ear,” a craving to hear something new; an “itching foot,” a craving for travel.
But Shakespeare gave us the “itching palm.” It is to be found in Julius Caesar (1601), Act IV, scene 3.
Cassius has come to the tent of Brutus to voice certain complaints, especially to criticize Brutus for condemning a friend of Cassius for taking bribes.
In reply Brutus says: “Let me tell you, Cassius, you your selfe Are much condemn’d to haue an itching Palme.”