And the king and his men went to Jerusalem against the Jebusites, the inhabitants of the land, who said to David, “You will not come in here, but the blind and the lame will ward you off”—thinking, “David cannot come in here.” 7 Nevertheless, David took the stronghold of Zion, that is, the city of David. 8 And David said on that day, “Whoever would strike the Jebusites, let him get up the water shaft to attack ‘the lame and the blind,’ who are hated by David's soul.” Therefore it is said, “The blind and the lame shall not come into the house.” 9 And David lived in the stronghold and called it the city of David. And David built the city all around from the Millo inward. 10 And David became greater and greater, for the Lord, the God of hosts, was with him.That was a jarring read for us. It seems quite uncharacteristic that David, who elsewhere graciously took in Mephibosheth who was lame in his feet and who repeatedly wrote about God's kindness toward the needy, would "hate" the lame and the blind.
So, I looked up the passage in a few commentaries and found that, according to some commentators, in this context the "blind and the lame" refers to idols. The Jebusites had idols, which were affronts to the one true God and thus hated by David, made of some type of material. Of course these statues couldn't see or hear or talk or walk--they were handmade objects of wood or stone. They were blind and lame. Yet the Jebusites were using them to ward off David's attacks and were taunting him with them, believing their idols would help them. When David attacked, his men tore down the blind and lame idols.
While this seems the more likely explanation to me, there is another possibility. It's possible that the Jebusites thought their city so strong and impregnable that they believed the "blind and lame" could defend it from David's attacks. And that this was used to provoke David so that he hated the Jebusites who were saying these things to him.
