Isaiah 30:17

17 A thousand shall flee at the threat of one, at the threat of five you shall flee, until you are left like a flagstaff on the top of a mountain, like a signal on a hill.

Isaiah 30:17 Meaning and Commentary

Isaiah 30:17

One thousand [shall flee] at the rebuke of one
A troop of horse, consisting of a thousand men, shall flee upon the attack and onset of a single person, so dispirited should they be, and so possessed of the fear of the enemy; what was promised to them with respect to their enemies is here turned against them, ( Leviticus 26:7 Leviticus 26:8 ) ( Deuteronomy 32:30 ) : at the rebuke of five shall ye flee;
being attacked by a very small number, the whole army should run away: this denotes with what ease they should be routed, and put to flight; and is to be understood, not of what would be at the present time, but of what should come to pass hereafter, when the Chaldean army should come against them; till ye be left as a beacon upon the top of a mountain;
or, "as the mast of a ship", so the Septuagint and other versions. Jarchi says it signifies a high tree, or tall piece of wood fixed in the earth, like a ship's mast F16, set up to give warning of an enemy's approach, and when, and where, sometimes fires used to be kindled; hence the Targum is,

``till ye are left as a burning torch on the top of a mountain.''
The Syriac version renders it, "as a wild ass", solitary and alone: and as an ensign on a hill;
erected as a trophy of victory. The design of the metaphors is to show that there should be few that should escape falling into the enemy's hand, here and there one, that should he scattered about, and be very thin, as beacons and signs are, and should be warnings to others of pursuing the same foolish and sinful methods and practices.
FOOTNOTES:

F16 So Ben Melech says, it is a high piece of wood in a ship, on which they hang an ensign or flag; and so he interprets the ensign in the next clause of a veil, so called, because they lift it up upon the mast.

Isaiah 30:17 In-Context

15 For thus said the Lord God, the Holy One of Israel: In returning and rest you shall be saved; in quietness and in trust shall be your strength. But you refused
16 and said, "No! We will flee upon horses"— therefore you shall flee! and, "We will ride upon swift steeds"— therefore your pursuers shall be swift!
17 A thousand shall flee at the threat of one, at the threat of five you shall flee, until you are left like a flagstaff on the top of a mountain, like a signal on a hill.
18 Therefore the Lord waits to be gracious to you; therefore he will rise up to show mercy to you. For the Lord is a God of justice; blessed are all those who wait for him.
19 Truly, O people in Zion, inhabitants of Jerusalem, you shall weep no more. He will surely be gracious to you at the sound of your cry; when he hears it, he will answer you.