In the ancient world, to measure something was to claim authority over it. When Zechariah sees a man with a measuring line (Zechariah 1:16, 2:1), it is not a literal surveying project for a stone wall. It is a legal declaration that God has returned to inhabit His people. The "line" represents the divine standard by which the New Covenant community is defined and protected.
While the post-exilic remnant was rebuilding a physical structure, the prophecy looked toward the first century. In Revelation 11, John is given a measuring reed to measure the temple of God, while the "outer court" is left to be trampled. This marks the Covenant Transition: God was measuring out the spiritual remnant (the Church) for protection while leaving the physical, apostate system of Jerusalem to the judgment of AD 70.
The measuring line is now "stretched forth" over the global body of Christ. There is no longer a need for physical borders or stone walls because the Church is the "unwalled city" (Zechariah 2:4) protected by the fire of the Spirit. The architecture of God is now human hearts, not limestone blocks.