2 Samuel 1:18

“(Also he bade them teach the children of Judah [the use] of the bow, etc.] These words, with what follow in this verse, are rightly put into a parenthesis, since they do not begin nor make any part of the elegiac song, or lamentation of David; and are here inserted to show, that, amidst his sorrow and lamentation, he was not unmindful of the welfare of the people, and to provide for their defence and security; and therefore gave orders that care should be taken, especially in the tribe of Judah, which was his own tribe, and where he had the greatest authority, and for whom he might have the chiefest concern, that they should be trained up in military exercises, learn the art of war, and the…”

“The use of the bow - Omit “the use of.” “The bow” is the name by which this dirge was known, being so called from the mention of Jonathan’s bow in 2 Samuel 1:22. The sense would then be: And he commanded them to teach the children of Israel the song called Kasheth (the bow), i. e. he gave directions that the song should be learned by heart (compare Deuteronomy 31:19). It has been further suggested that in the Book of Jasher there was, among other things, a collection of poems, in which special mention was made of the bow. This was one of them. 1 Samuel 2:1-10 was another; Numbers 21:27-30 was another; Lamentations 2:0 was another; Lamentations 3:0 was another; Jacob’s blessing Genesis 49:0;…”

“Judah - These he more particularly teacheth, because they were the chief, and now the royal tribe, and likely to be the great bulwark to all Israel against the Philistines, upon whose land they bordered; and withal, to be the most true to him, and to his interest. The bow - That is, of their arms, expressed, under the name of the bow, which then was one of the chief weapons; and for the dextrous use whereof Jonathan is commended in the following song: which may be one reason, why he now gives forth this order, that so they might strive to imitate Jonathan in military skill, and to excel in it, as he did. Jasher - It is more largely and particularly described in the book of Jasher. 2 Kings (2…”

“1:18 The extrabiblical Book of Jashar is no longer available. It was probably an Israelite epic poem or an anthology of poetry that covered, at minimum, Joshua’s conquest of Canaan (see Josh 10:13) and the ascension of David.”

“teach: Gen 49:8; Deu 4:10 bow: Kasheth, or the bow, was probably the title of the following threnody; so called, in the oriental style, because Saul's death was occasioned by that weapon, and because the bow of Jonathan, out of which "the arrow was shot beyond the lad," ( Sa1 20:36), is celebrated in this song. the book: Jos 10:13 Jasher: or, the upright, So LXX επι βιβλιου τον ευθους; Targum, siphra deooritha, "the book of the law;" the Arabic, "the book of Ashee. this is the book of Samuel." This book was probably a collection of divine odes, written to commemorate remarkable events. 2 Kings (2 Samuel) 1:19”