Psalms 45:5 - Matthew Poole's English Annotations on the Holy Bible

Thine arrows; the same thing for substance with the sword, Psalms 45:3, both noting the instruments by which he conquers his enemies; which is no other than his word, which is sharp and powerful, and pierceth the hearts of men, Hebrews 4:12; which also first wounds sinners, and then heals them; and which is for the fall as well as for the rising of many, Luke 2:34, and for judgment as well as for mercy, 1 Thessalonians 9:39; to some a savour of death, and to others a savour of life, 2 Corinthians 2:16; and therefore is fitly compared to arrows; which title is sometimes given to words, as Psalms 64:3, and frequently to God's plagues or judgments, Deuteronomy 32:23 Psalms 18:14, Psalms 64:7, such as the word becomes to ungodly men by their own fault. And these metaphorical weapons are oft ascribed to Christ, who hath a bow, Revelation 6:2, and weapons of warfare, 2 Corinthians 10:4, and whose mouth God is said to make a sword and an arrow, Isaiah 49:2. Of the king's enemies, i.e. of thine enemies; the third person being put for the second, as is usual in prophetical writings; which here may seem to have some emphasis, as describing the persons against whom he shot his arrows, and the reason why he did so, because they were the enemies of his kingdom, and would not have him to reign over them, Luke 19:27. The people fall under thee; either as slain by thine arrows; or as prostrate at thy feet, after the manner of conquered persons, Psalms 18:38, Psalms 20:8. According to this and many other translations the words are transplaced, which in the Hebrew lie thus, Thine arrows are sharp, whereby the people do fall under thee, in the heart (i. e. in the midst, which is oft called the heart, as Exodus 15:8 Deuteronomy 4:11. And so it may be here; for the army, as such, hath no heart, properly so called. And so this is fitly alleged, as a proof of the sharpness and force of his arrows, that they not only wound those who march in the front, but even those who are in the midst of the army, where they may seem secure, and out of-their reach) of the king's enemies. But the middle words may be, and are by many, included within a parenthesis, and so they may agree with our translation thus, Thine arrows are sharp (for the people fall under thee, which is an evidence of their sharpness) in the heart (or, against the heart; or, piercing into the heart; which is an easy and usual ellipsis) of the king's enemies.