2 Samuel 5:7-9

Complete Jewish Bible

⁷ Nevertheless, David captured the stronghold of Tziyon, also known [now] as the City of David. ⁸ What David said on that day was, “In order to attack the Y’vusi, you have to climb up [from the spring outside the city] through the water tunnel. Then you can do away with those [so-called] ‘lame and blind’” (whom David despises — hence the expression, “The ‘blind and lame’ keep him from entering the house”).

⁹ David lived in the stronghold and called it the City of David. Then David built up the city around it, starting at the Millo [earth rampart] and working inward.