31:19-24 The Israelites had to purify themselves according to the law, and to abide without the camp seven days, though they had not contracted any moral guilt, the war being just and lawful, and commanded by God. Thus God would preserve in their minds a dread and detestation of shedding blood. The spoil had been used by Midianites, and being now come into the possession of Israelites, it was fit that it should be purified.Brass - Render copper. See Genesis 4:22 note. The verse is curious as illustrating the variety of metals in use at this early date for domestic purposes. All these metals were common in Egypt centuries before the date of the Exodus. 19-24. abide without the camp seven days: whosoever hath killed any person … purify both yourselves and your captives—Though the Israelites had taken the field in obedience to the command of God, they had become defiled by contact with the dead. A process of purification was to be undergone, as the law required (Le 15:13; Nu 19:9-12), and this purifying ceremony was extended to dress, houses, tents, to everything on which a dead body had lain, which had been touched by the blood-stained hands of the Israelitish warriors, or which had been the property of idolaters. This became a standing ordinance in all time coming (Le 6:28; 11:33; 15:12). No text from Poole on this verse.

Only the gold, and the silver, the brass, the iron, the tin, and the lead. These are excepted, and, though unclean, are not to be purified by washing, but in another way, by fire, as follows; all these metals were well known in those early times, and were made use of for instruments and vessels of various sorts. Only the gold, and the silver, the brass, the iron, the tin, and the lead,