| Gill's Exposition of the Entire Bible Appoint a way,.... Mark out a way, describe a road, draw one out upon the ground, or point out one upon a table, or tile: that the sword may come; in which the sword will come; or those that kill with the sword, as the Targum, even the Chaldean army under Nebuchadnezzar: to Rabbath of the Ammonites; which was the metropolis of the Ammonites, and is now called Philadelphia, as Jerom writes; it is so called, to distinguish it from others of the same name; see 2 Samuel 12:26, and to Judah in Jerusalem, the defenced city; which was so both by nature and art; it had mountains round about it, and had been fortified by several kings from the time of David, as Solomon, Hezekiah, and Manasseh. Judah is said to be in it; though it would seem more properly that Jerusalem was in Judah, because that people from all parts of Judah, upon hearing of the king of Babylon's intention and near approach to invade their land, fled to Jerusalem, being a fortified place, for security. Now the prophet is bid to describe a way hither; not that one and the same way led to Rabbath and Jerusalem; but he was to describe a way from the place where Nebuchadnezzar stopped, which led to Rabbath, and another which led to Jerusalem.
Geneva Study BibleMark a way, that the sword may come to Rabbah of the Ammonites, and {p} to Judah in Jerusalem the fortified. (p) That is, to the tribe of Judah that kept themselves in Jerusalem.
Wesley's Notes 21:20 To Judah - The Jews.
Jamieson-Fausset-Brown Bible Commentary20. Rabbath of the Ammonites-distinct from Rabbah in Judah (2Sa 12:26). Rabbath is put first, as it was from her that Jerusalem, that doomed city, had borrowed many of her idols. to Judah in Jerusalem-instead of simply putting "Jerusalem," to imply the sword was to come not merely to Judah, but to its people within Jerusalem, defended though it was; its defenses on which the Jews relied so much would not keep the foe out.
Matthew Henry's Concise Commentary21:18-27 By the Spirit of prophecy Ezekiel foresaw Nebuchadnezzar's march from Babylon, which he would determine by divination. The Lord would overturn the government of Judah, till the coming of Him whose right it is. This seems to foretell the overturnings of the Jewish nation to the present day, and the troubles of states and kingdoms, which shall make way for establishing the Messiah's kingdom throughout the earth. The Lord secretly leads all to adopt his wise designs. And in the midst of the most tremendous warnings of wrath, we still hear of mercy, and some mention of Him through whom mercy is shown to sinful men. | 
