The current Code of Canon Law (1983) states:
“Can. 855 Parents, sponsors, and the pastor are to take care that a name foreign to Christian sensibility is not given.”
(This topic is also discussed over at the Canon law blog of Dr. Peters)
A name can be given if it is not ‘foreign to Christian sensibility’. The Latin, ‘a sensu christiano alienum’, could also be translated as ‘foreign to Christian understanding’. There is currently no requirement in Church law that parents name their child after a Saint. But which names are foreign to Christian understanding? A name from a religion other than Judaism or Christianity would be foreign to the understanding of Christianity. A name from a celebrity in sinful secular society would also be similarly foreign. However, a family name, or a common name in a particular nation or ethnic group, even if it is not a traditional Christian name, would not be foreign. There is currently a wide latitude, in my interpretation, to the names that can be given to a child.
The old Code of Canon law (1917), 761 stated: “Pastors should take care that a Christian name is given to those whom they baptize; but if they are not able to bring this about, they will add to the name given by the parents the name of some Saint and record both names in the book of baptisms.”
This rule was problematic because most Saints, especially at that point in history (prior to Pope John Paul II naming more Blesseds and Saints than all past Popes put together), were from European nations. The effect of the law was to require a European name, or a selection from relatively few non-European Saint names, to be imposed on the Catholics in a non-European nation. Even today, most Saints, especially those who are more well-known, are from Europe.
I think the old Code could be reasonably interpreted such that ‘a Christian name’ is not necessarily a Saint’s name. So a family could name a child after a family member or friend or well-known person in their local community, if the person was a faithful Catholic Christian. And this interpretation still applies to the new Code. A Saint’s name need not be chosen.
To make this point even clearer, consider what would happen if the Church had instituted the rule that only a Saint’s name could be used, beginning in the first century A.D. There were only a few persons called ‘Saint’ at that time, and there was no process for canonization. All children would then have had one of only a few possible names. Then if any of them became Saints, all the new Saints would have the same names as that first set of Saints. There would be hundreds of Saint John’s and hundreds of Saint Peter’s etc.
My point is not so much about this one Canon, but about Canon Law in general. Except when a Canon is a direct expression of a doctrine of faith or morals, that Canon is changeable by the Church. And it can be dispensed in particular cases by the Pope, and/or the Holy See, and/or the local Bishop. And it can sometimes be ignored or contradicted by the faithful, without sin or fault.