“I AM WHO I AM,” God told Moses (Exod. 3:14). God has a name. But, unlike ours, his Name perfectly expresses what and who he is. “Jeff” is an arbitrary noise, an arbitrary signature, that has no intrinsic connection to a person who by no means has to exist. “Jeff” expresses nothing.
Our fear of blood might explain why the feast day we celebrate today is often called Holy Name rather than the Circumcision of Christ (evidently the more common name in days gone by)