Our Sages taught that Nega’im-afflictions come upon a person for one of seven reasons, one of them being miserliness, such as when a person refuses to lend his utensils to his neighbor. In the end, as a result of the nega-affliction on his home, he will be forced to totally demolish his home. Nowadays, although the Holy One in His mercy does not visit our homes with nig’ei batim, nevertheless, miserliness causes blight to come upon a person’s possessions. This is an instance of a “measure for measure” type of punishment. Since the person did not want to let other enjoy his possessions, and he does no kindness with what he has, so will the Attribute of Justice treat him and his possessions — without kindness and mercy. The inevitable result will be that his wealth will collapse, for nothing can continue under the attribute of Strict Justice.
Our Sages also said: “Be careful that you do not withhold mercy, for whoever withholds mercy is compared to idolatry and he throws the yoke of Heaven off of himself.” That is, since the miser trusts only his own gold and silver, he obviously does not put his trust in Hashem. The Torah alludes by saying: Gods of silver and gods of gold do not make for yourselves (Shemos 20:20).