What's in a Name?
Would you please explain the significance of names in Judaism? Does it matter what name a person was given, or gives to his children?
Naming is taken very seriously in Judaism. We find that the names of all the important and central figures of the Torah were significant and given for a reason. This is because a name is bound with, and has an effect on, the spiritual character of a person. It is therefore of utmost importance to choose a name which fits this lofty purpose.
According to Jewish sources, despite the fact that prophecy has ceased in general, there are still some residual situations and people in which inklings of prophecy appear. One of them is regarding parents’ naming their children. So a Jewish name given at birth is very significant and contains within it a divinely inspired connection to the person’s spiritual essence.
In addition, such a name expresses and enhances the unique qualities and powers of the individual, forming a type of aura that accompanies a person through life. It is for these reasons that it is so important to give traditionally acceptable names of righteous and holy people or things.
This is the basis for the common practice to name children after relatives or rabbis and rebbetzins of outstanding spiritual and moral standing. Sefardim often do so for people who are still living; Ashkenazim do so only after the departed. In any case, this is viewed as actually establishing a spiritual connection between the child and the namesake. (According to some opinions, the full name of the namesake should be used and not part of the name, or combined with the name of another person – as naming after different grandparents together.)
Since the name is so intimately entwined with the essence of a person and also has such a significant influence on what happens in a person's life, certain teachings stress the importance of avoiding nicknames, diminutives or parts of names which could change or limit the flow of spiritual influence otherwise derived from a person's full name. So, for example, Ya’akov Yosef should be called just that and not Yankel or Yosi. Some are of the opinion that two names should not be given in the first place, i.e. either Ya’akov or Yosef but not both.
Finally, since names are viewed as being so influential, while they are rarely changed, names are often added under special circumstances. So someone who is seriously ill might have the name Chaim, life, added to his name. Similarly, a person who is lacking something very important in life such a spouse, livelihood or tranquility might have a relevant name added whose influence may improve what's lacking in his life. Sometimes names are added to increase compatibility between couples both before and after marriage.