Many have a custom of wearing white clothing on Yom Kippur in emulation of the ministering angels. Some people wear a kittel, a white robe worn over the clothing. Because it is similar to the burial shroud, it serves to remind us of man's mortality and the need for teshuvah. The kittel should not be decorated with gold, for gold recalls the sin of the golden calf and that which was a source of prosecution for the Jew cannot be transformed into a defender. It is permissible, however, to decorate the kittel with silver, for silver is close to white, symbolizing purity and mercy.
It is a tradition in all Jewish communities to wear a large tallit on Yom Kippur evening. The white of the tallit also serves to suggest purity and mercy.
The story is told of a great righteous man who stood before the congregation one Yom Kippur eve, and addressed his fellow Jews, who were all clad in white garments and wrapped in their white tallitot.
My brothers and sisters, children of Israel! Take to heart that it is in white garments like these we are wearing now, that we shall ascend to the World to Come to be judged and give our accounting before the King of all kings, the Holy One, blessed is He.
Let us then imagine that we are standing in this clothing before the Throne of Glory to be judged and give our final accounting. We should have true remorse, for one who stands before the Throne of Glory is truly remorseful. But, my brothers and sisters, repentance does not avail after death-only now does it avail! Let us truly regret all our sins and accept upon ourselves that we shall sin no more, and let us ask the King who grants forgiveness that He grant us forgiveness and atonement.