Verse 1: And the LORD said unto Joshua, (Deut. 1:21; 7:18; 31:8; Josh. 1:9) Fear not, neither be thou dismayed: take all the people of war with thee, and arise, go up to Ai: see, (Josh. 6:2) I have given into thy hand the king of Ai, and his people, and his city, and his land…
[Fear not] It is not to be marveled at that Joshua has need of a new confirmation, who observed the corruption of his compatriots, and in what position he would be, etc. (Masius).
[All the multitude of fighters] Hebrew: all the people of war (Montanus), apt for war (Junius and Tremellius, Massius); all the warlike men (Septuagint, Arabic, similarly Vatablus). Why so? Responses: 1. To suppress the fear of all. 2. So that the circumstances of all might be equal in the first plunder (Masius, Lapide), since all had abstained from the spoils of Jericho (Bonfrerius). Or it is thus to be taken, that is to say, that no one is to be led out that is not strong in martial courage: For a multitude would be an impediment in feigning flight. Although it is able to be spoken to this purposes, that part of the troops proceeded into the valley, the rest remained in the camp (Masius).
Take all the people of war with thee; partly to strengthen them against those fears which their late defeat had wrought in them; and partly that all of them might be partakers of this first spoil, and thereby be encouraged to proceed in their work. The weak multitude were not to go, because they might have hindered them in the following stratagem; and it was but fit that the military men who run the greatest hazards, should have the precedency and privilege in the spoils.
[Go up] We are said to go up into the North, to go down into the South: Thus, one goes up into Babylon; in Hosea 8:9, they have gone up into Assyria (Ibn Ezra in Drusius). The command to ascend stands for an argument that Ai was a more elevated place (Masius).
 Hebrew: וַיֹּ֙אמֶר יְהוָ֤ה אֶל־יְהוֹשֻׁ֙עַ֙ אַל־תִּירָ֣א וְאַל־תֵּחָ֔ת קַ֣ח עִמְּךָ֗ אֵ֚ת כָּל־עַ֣ם הַמִּלְחָמָ֔ה וְק֖וּם עֲלֵ֣ה הָעָ֑י רְאֵ֣ה׀ נָתַ֣תִּי בְיָדְךָ֗ אֶת־מֶ֤לֶךְ הָעַי֙ וְאֶת־עַמּ֔וֹ וְאֶת־עִיר֖וֹ וְאֶת־אַרְצֽוֹ׃
 Hebrew: כָּל־עַ֣ם הַמִּלְחָמָ֔ה.