Dow's Process for the manufacture of phenol When chlorobenzene ($\ce{C6H5Cl}$) reacts with aqueous ($\ce{NaOH}$) solution it first forms sodium phenoxide ($\ce{C6H5ONa}$), and then phenol upon reacting with $\ce{H+}$.

But my question is, why can't $\ce{Na}$ directly replace $\ce{Cl}$ from chlorobenzene by breaking $\ce{Na-O}$ bond instead of breaking $\ce{O-H}$ bond?
The mechanism of this reaction is that $\ce{NaOH}$ being a strong base with some extreme conditions abstracts  H from C adjacent to C containing Cl while Cl also leaves.

This creates benzyne as an intermediate. 

Subsequent addition of $\ce{NaOH}$ forms the phenoxide ion.