Dockerfile Service failed to build: COPY failed: Forbidden path outside the build context: ../../../../*

I want to specify files outside of the dockerfile location. Below is my dockerfile and I get this error: "Step 2/3 : COPY ../../../../wildfly/standalone /opt/jboss/wildfly/
Service ‘wildfly’ failed to build: COPY failed: Forbidden path outside the build context: ../../../../wildfly/standalone ()"
How can I reference the root of the directory or reference a file outside of the dockerfile workspace?

`FROM jboss/wildfly:10.1.0.Final

COPY ../../../../wildfly/standalone /opt/jboss/wildfly/
`

Source: Docker Questions