Verse 18: And the LORD said unto Joshua, Stretch out the spear that is in thy hand toward Ai; for I will give it into thine hand. And Joshua stretched out the spear that he had in his hand toward the city.
[Lift the shield, נְ֠טֵה בַּכִּיד֤וֹן] Extend, etc. (Montanus); rather, lift (Vatablus). Question 1: What is the כִּידוֹן here? Response: This word occurs here, and in verse 26, and in 1 Samuel 17:6, 45, and in Job 39:23; 41:29, and in Jeremiah 6:23; 50:42; but not elsewhere. Some translate it, shield: thus Josephus, Theodotion, and Symmachus on this passage; thus the Septuagint, Syriac, and Arabic in Samuel; thus the Chaldean and Jerome in Jeremiah (Bochart’s A Sacred Catalogue of Animals 1:2:8:136). Thus Masius and Grotius. This it appears to signify out of 1 Samuel 17:6 and Jeremiah 6:23 (Grotius). Others: spear, or lance (thus Kimchi, Rabbi Salomon, Rabbi Levi, and Pomarius in Bochart’s A Sacred Catalogue of Animals, Syriac, Jonathan, Bochart’s A Sacred Catalogue of Animals). Spear (Munster, Pagnine, Vatablus), banner (Junius and Tremellius, Piscator). Extend on the banner, in the place of, extend thy hand with the bannder, as it is in Exodus 8:5. This is confirmed out of the following verse and verse 26 (Piscator). The standard-bearing spear (Junius). On the end of the spear was a banner (Vatablus, Hebrews in Masius). But the Hebrews add this of their own (Masius). The Septuagint here translate it γαισὸν, which is a sort of Gallic (and Libyan [Masius]) dart (Bochart’s A Sacred Catalogue of Animals 1:2:8:136, Masius). They explain it as ἐμβόλιον ὁλοσίδηρον (a javelin of iron), or κόντιον (a pike) (Grotius); I would prefer ἀκόντιον, a dart; although even Suidas explains it as κοντὸν/pike (Bochart’s A Sacred Catalogue of Animals 1:2:8:136). Some take γαισὸν as shield (thus Bonfrerius, Serarius). By which they show that they have not made much progress in this literature (Bochart’s A Sacred Catalogue of Animals). Question 2: To what end was he lifting this? Responses: 1. So that he might give a sign to those that were in ambush (Vatablus, thus Junius, Lyra, Tostatus and Josephus and Theodotion in Serarius, Menochius, Lapide): then also to those fleeing, so that they might turn their faces toward their enemies (Junius). To others this is not satisfying. 1. Joshua was a great distance from the ambush, and the city with the valley was lying between Joshua and the ambush (Serarius, Bonfrerius). [But Menochius responds:] The liers in wait were not seeing the shield, but, as it is wont to be done, some were keeping watch in a high place, whence they might alert the liers in wait (Menochius). 2. Concerning such a sign nothing was agreed previously, but it was extemporaneously suggested by God (Bonfrerius out of Serarius). [A response is able to be furnished out of Lapide:] This sign was given to them by Joshua (although Scripture does not express it) (Lapide). 3. Then no reason is able to be rendered why he did not let the shield drop until after the fighting, etc., verse 26 (Bonfrerius). If it was only a sign, with that given, he was able to let his hand fall. 2. Others, therefore, maintain that this was done for a sign and mystery of another matter (Serarius). God willed that Joshua by this lifting of his shield as the moral cause concur unto the destruction of the city of Ai, just like Moses in Exodus 17, etc. (Bonfrerius out of Masius, Serarius out of Cajetan, Calvin, Mayer). It is evidence of this, that he does not draw back his hand until the fighting is over (Masius, Bonfrerius). Then it follows, for I will give it into thy hand, בְיָדְךָ; through thy hand, or by thy hand, morally concurring, I have decreed to deliver it (Bonfrerius out of Masius). I will that this victory depend upon thine hand stretched out with thy shield. In other respects he was sufficiently certain of victory before. Question: Why did God will that he stand idle in one place, detained for the stretching forth of the shield? Response: So that the full glory of the victory might be reserved for God, whose presence he points out as if with a finger, merely extending his hand against the enemy city. Here Joshua shows his obedience, while for this ridiculous, as it appeared, gestured he kept himself free, I would not say despising the glory, but practicing an ignoble idleness (Malvenda). Question: By what sign then did the liers in wait know when to break in upon the city? Responses: Either, 1. by the clamor of the citizens sallying forth from the city (Bonfrerius out of Serarius). It is likely that the sallying forth of the citizens was able to be seen by the ambush, at least to some extent, since they pursued the Israelites toward the North (Masius). Or, 2. by a certain sounding of the trumpet, or similar method (Bonfrerius). Or, 3. by the author and director, God, prompting the commander of the ambush, either by internal inspiration, or by a more external and sensible sign (Bonfrerius out of Masius). I refer it to the hidden efficacy of God, by which He suggested to His people all the right times of the matter to be conducted (Masius). And thus that which follows is able to be understood, that immediately, as Joshua lifted his shield, the ambush sallied forth, that is, with God prompting that it was the right time for the execution of the plan (Bonfrerius). But Joshua himself, who was holding the shield or spear, was not sufficiently able to know when the city was at last emptied of the entire garrison and fit for ambush, except by the secret prompting of God (Masius).
The spear, or, thy banner; or there might be some banner in the end of his spear. This was prescribed and practised, either, 1. For a sign to his host present with him, to stop their flight, and make head against the pursuers; or, 2. For a signal to the liers in wait, as may seem from verse 19, who, though they were at some distance, might know this from persons whom they had set in some high and convenient places to observe Joshua’s motion, and to give notice from one to another, and that speedily, as is common in such cases, until it came to the whole ambush; or, 3. As a mystical token of God’s presence and assistance with them, and of their victory; or as a mean by God’s appointment contributing to their good success, as the like posture of Moses lifting up his hand was, Exodus 17:11, 12, which may be the reason why he continued this posture till the enemies were all destroyed, Joshua 8:26; whereas if it had been a signal only, it was sufficient to do it for a little while. I know no reason why all these ends might not be joined together.
 Hebrew: וַיֹּ֙אמֶר יְהוָ֜ה אֶל־יְהוֹשֻׁ֗עַ נְ֠טֵה בַּכִּיד֤וֹן אֲשֶׁר־בְּיָֽדְךָ֙ אֶל־הָעַ֔י כִּ֥י בְיָדְךָ֖ אֶתְּנֶ֑נָּה וַיֵּ֧ט יְהוֹשֻׁ֛עַ בַּכִּיד֥וֹן אֲשֶׁר־בְּיָד֖וֹ אֶל־הָעִֽיר׃
 נָטָה can signify to stretch out, or to incline.
 1 Samuel 17:6: “And he had greaves of brass upon his legs, and a target (וְכִידוֹן) of brass between his shoulders.”
 1 Samuel 17:45a: “Then said David to the Philistine, Thou comest to me with a sword, and with a spear, and with a shield (וּבְכִידוֹן): but I come to thee in the name of the Lord of hosts…”
 Job 39:23: “The quiver rattleth against him, the glittering spear and the shield (וְכִידוֹן).”
 Job 41:29: “Darts are counted as stubble: he laugheth at the shaking of a spear (כִּידוֹן).”
 Jeremiah 6:23a: “They shall lay hold on bow and spear (וְכִידוֹן); they are cruel, and have no mercy; their voice roareth like the sea…”
 Jeremiah 50:42a: “They shall hold the bow and the lance (וְכִידֹן): they are cruel, and will not shew mercy…”
 David ben Isaac de Pomis (1525-1593) was an Italian physician, philosopher, and Rabbi. He produced an important Hebrew, Latin, and Italian dictionary (Zemah David).
 Exodus 8:5a: “And the Lord spake unto Moses, Say unto Aaron, Stretch forth thine hand with thy rod (נְטֵ֤ה אֶת־יָדְךָ֙ בְּמַטֶּ֔ךָ) over the streams, over the rivers, and over the ponds…”
 Suidas was the compiler of the Suda, an encyclopedia containing more than thirty thousand entries concerning the ancient Mediterranean world. It was probably composed in tenth-century Byzantium.