David said on that day, “Whoever attacks the Jebusites must approach the ‘lame’ and the ‘blind’ who are David’s enemies ¹  by going through the water tunnel.” ²  For this reason it is said, “The blind and the lame cannot enter the palace.” ³ 

Then the king and his men advanced to Jerusalem ¹  against the Jebusites who lived in the land. The Jebusites ²  said to David, “You cannot invade this place! Even the blind and the lame will turn you back, saying, ‘David cannot invade this place!’”