"your my rock of gibaltar"

how knows where the saying "your my rock of gibaltar" comes from.

From the Rock of Gibraltar - between Spain and North Africa.

It is a solid, permanent, unchanging feature (or it appears to be to humans with our perception of time. In geological time it will presumably change.)

To say that someone is 'my Rock of Gibraltar' means that they are a fixed, permanent part of my life which can be relied upon.

DFG