According to Lacan, the name of the father is the instrument of inscription into the symbolic order.  It generates and channels desire, which ultimately refers back to a subject that yearns to be given a name and a place, interprets inscrutable signs about whether it has been given these or not, and is ultimately and tragically in excess of any possible name.   The name of the father is both the father's name and the father's power to name. 

of course the father's name is YHVH, and its four letters refer to the four Olamot of Qabala.  But the father is also dead.

The decline of the name of the father is a major theme in the late Lacan. We live in psychotic times; we are mentally ill because we aren’t unconsciously subjugated to heroic projects that exceed our individuality. “Patriarchy” died long ago; if anything, modern 21st century humans could use a father, or some kind of symbolic orientation for their suffering.  Some believe that anything can serve as the nom du pere - any kind of project, identity or conviction.  

This may be so, but not all names are equally valid.  According to Transcendental Qabala, the only valid name, replacing the father's name, is "Ark" 

What distinguishes Ark from all other names?  The fact that it unconditionally privileges love