And the remnant of the trees of his forest shall be a number. [1] When he adds that the remnant of them will be a number, he employs a Hebrew idiom to express that they will be few; and thus he only confirms the former statement, that the devastation produced, after the calamity which God will bring on the Assyrians, will be so great that there will be no difficulty in counting them. That a child may number them. He goes so far as to say, that they will be so few that those who are left of them may be counted even by a child; for children have difficulty in counting as far as three or four. Accordingly, the kingdom of the Assyrians was formerly like some vast forest; but when the trees have been hewn and thrown down, those which are left are few, and scattered at great distances from each other.

Footnotes

1 - And the rest of the trees of his forest shall be few. (Margin, Heb. number.) -- Eng. Ver.

And the rest of the trees - Keeping up still the image of a large and once dense forest, to which he had likened the Assyrian army. 'The rest' here means that which shall be left after the threatened judgment shall come upon them.
That a child may write them - That a child shall be able to number them, or write their names; that is, they shall be very few. A child can number or count but few; yet the number of those who would be left, would be so very small that even a child could count them with ease. It is probable that a few of the army of Sennacherib escaped (see the note at Isaiah 37:37); and compared with the whole army, the remnant might bear a striking resemblance to the few decaying trees of a once magnificent forest of cedars.

And the rest of the trees of his forest shall be few,.... Which were left unconsumed, that escaped this destruction, those of the Assyrian army that fled with Sennacherib their king; which, the Rabbins say (r), were no more than ten, as Jarchi and Kimchi observe; yea, some say there were but five left who escaped, and name them, Sennacherib and his two sons, Nebuchadnezzar and Nebuzaradan:
that a child may write them; count them, and take down their names; and it may be understood of a military muster, and the sense be, that the army should be reduced to so small a number by this stroke upon them, that there would be no need of an able muster master to take the account of them, a child would be equal to such a task. The Targum is,
"and the rest of his warriors shall fail, that the people shall be a small number, and shall be reckoned a weak kingdom.''
(r) T. Bab. ib. fol. 95. 2. Praefat. Echa Rabbati, fol. 41. 1.

rest--those who shall survive the destruction of the host.
his forest--same image as in Isaiah 10:18, for the once dense army.
child . . . write--so few that a child might count them.

The rest - The remainder of that mighty host.