'Walls' in the Bible

Therefore, thus says the Lord, “I have returned to Jerusalem with mercy and compassion. My house shall be built in it,” says the Lord of hosts, “and a measuring line shall be stretched out over Jerusalem.”’

and he said to the second angel, “Run, speak to that young man, saying, ‘Jerusalem will be inhabited [like villages] without walls [spreading out into the open country] because of the great number of people and livestock in it.