It is difficult to imagine “too much kindness” since being kind to others is one of the great pillars of Judaism. In Hebrew this is called “chessed”. We are taught that the world is sustained by three things, one of them being acts of loving-kindness (Pirkei Avot 1:2).
However, there may be times when one should reign in this noble character trait: for example if a certain action will adversely affect one’s family harmony or extremely impoverish the giver. And sometimes giving a person what he wants is actually bad for the recipient and the “kind” thing to do would be to deny the help requested. For example a drunk who asks for money will only be hurt by giving him money to feed his habit. Real kindness would be to do something to help sober him up if possible.
But in general, this trait of chessed is a central part of being Jewish, and is actually a part of our “Jewish DNA” that was inherited from our Patriarch Abraham. As the Talmud teaches: "Whoever is merciful to others is clearly a descendant of Abraham our forefather, and whoever is not merciful to others is clearly not be his descendant."
