Thou knowest - what Joab - did to me - He did every thing bad and dishonorable in itself, in the murder of Abner and Amasa, and indeed in the death of the profligate Absalom.
Shed the blood of war - upon his girdle - and in his shoes - He stabbed them while he pretended to embrace them, so that their blood gushed out on his girdle, and fell into his shoes! This was a most abominable aggravation of his crimes.

Moreover thou knowest also what Joab the son of Zeruiah did unto me,.... In slaying Absalom, contrary to his orders, and in behaving insolently towards him on account of his mourning for him, and at other times; but as these things might not be personally known to Solomon, only by hearsay, this may respect his disloyalty towards him, in joining with Adonijah, who set himself up for king in his lifetime, and without his knowledge and consent; or it may respect the instances next mentioned, in which he did injury to the interest, honour, and character of David:

and, or "even",

what he did to the two captains of the host of Israel, unto Abner the son of Ner, and unto Amasa the son of Jether, whom he slew; to Abner who was under Ishbosheth, and Amasa under David, who had not only the promise of the post, but was actually in it when Joab slew him; and indeed out of envy to him for it:

and shed the blood of war in peace; when they were at peace with him, as if they had been in open war; and even under a pretence of friendship to them, asking of their peace and welfare, as if he meant nothing less than to behave peaceably towards them; hence the Targum is,

"whom he slew in craftiness:''

and put the blood of war upon the girdle that was about his loins,

and in his shoes that were in his feet; which particularly respects the affair of Amasa, whose blood he shed with his sword, that dropped out of its scabbard, girded upon his loins, and into which he put it again, all over bloody, and wore it girded upon his loins; and which he also stooped for when it fell, as if he was going to unloose or buckle his shoes, and into which the blood ran down when he stabbed him; and after this barbarous action marched on without any shame or remorse, with his bloody sword on his loins, and the blood of the murdered in his shoes.

thou knowest also what Joab . . . did--The insolent and imperious conduct of that general had not only been deeply offensive to the feelings (Sa2 18:5-15; Sa2 19:5-7), but calculated to bring reproach on the character, to injure the prospects, and endanger the throne of David. Passing over the injuries committed directly against himself, David dwelt with strong feelings on the base assassination of Abner and Amasa.

shed the blood of war in peace, &c.--The obvious meaning is, that in peace he acted towards them as if they had been in a state of warfare; but perhaps these graphic expressions might be designed to impress Solomon's mind more strongly with a sense of the malice, treachery, and cruelty by which those murders were characterized.