Rashi on the Former Prophets

To the Yevusi. The fortress of Tzion was called Yevus. [Its inhabitants] were from the descendants of Avimelech. They had two idols, one [depicting] a blind person and one [depicting] a lame person. They were made to represent Yitzhok and Yakov. [Placed] in their mouths was the oath Avrohom swore to Avimelech, This is why they were not displaced [from Tzion]. When Yerushalayim was conquored The tribe of Yehuda did not conquor the fortress [of Tzion], as the verse states, (Yehoshua, 15, 63). "However the Yevusim who lived in Yerushalyim, the descendants of Yehudah were unable to expel them. [About this verse] it is learned: Rebbe Yohoshua, the son of Levi said, They had the ability to [expel the Yevusim] but they were not permitted to.
And he said to Dovid. Whoever said it,
[The idols depicting] the blind and the lame These were their idols.

Whoever kills the Yevusi and touches [and destroys] the towers spire Whoever kills the Yevusi and has the strength to conquor the fortress.
And [the idols of] the lame. And destroys [the idols of] the lame and the blind which were abhorrent to Dovid.
Upon which they are saying. Upon which they are saying, "The blind one and the lame one," i.e., while the blind one and the lame one are here.
[Dovid] will not come Dovid will not come here. This is a shortened verse [because] it stated, "Whoever kills the Yevusi and touches [and destroys] the tower's spire" but [the verse] does not explain what happens to the person [who reaches the spire]. However, in Divrei Hayomim I, 11, 6) it explains, "Whoever kills the Yevusi first will be made a chief and a prince." Similar to this [we find]. "Therefore, whoever kills Kayin" (Bereishis 4, 14) and [that verse] does not explain what happens to the person [who kills Kayin] but from its context, it's understood that the language conveys rebuke and anger.
And touches [and destroys] the tower's spire. [This word] denotes the spire of a tower because that's where their idols were placed. [During] the days of Dovid, the generations of the oath had already passed.

From it's low wall and inwards. A surrounding low wall; they would fill it up with earth, the summit of the mound would be in it's middle, and it would slant in all directions, that is called a מלוא, and Dovid built houses on [the wall]. That low wall surrounded the fortress.

Dovid understood. When he saw all his endeavors succeeding, and the idol worshipping kings sending him a present.

Fanned out. They dispersed.

Into the plain of Perotzim. The plain of Perotzim
Like water bursting over [walls]. Like water bursting over the walls edge.

And Dovid burnt them. Dovid and his men burnt them.

The valley of Rephaim. It is next to Yerusholoyim [as can be seen] in the book of Yehoshua (15, 8).

From opposite the trees. From opposite the trees.

The sound of stepping on the tops of the trees. These are angels stepping on the tops of the trees that I am sending to help you.
Then shout [war whoops]. Lift up [and bring forth] the sound of war and the fear of the sword Galfer in Old French, and similarly [we find] "A dog will not sharpen its tongue [growl].