Here is an example of how important it is to compare Bible translations, especially when strting from the KJV or other older Bibles.
"And he brought forth the people that were therein, and put them under saws, and under harrows of iron, and under axes of iron, and made them pass through the brick-kiln: and thus did he unto all the cities of the children of Ammon. So David and all the people returned unto Jerusalem." 2 Samuel 12:31 (KJV)
My that David sounds like a monster, doesn't he?! Sawing, chopping and burning his captives. But lets look at some newer translations.
"And he brought out the people who were in it, and put them to work with saws and iron picks and iron axes, and made them cross over to the brick works. So he did to all the cities of the people of Ammon. Then David and all the people returned to Jerusalem." 2 Samuel 12:31 (NKJV)
"and brought out the people who were there, consigning them to labor with saws and with iron picks and axes, and he made them work at brickmaking. He did this to all the Ammonite towns. Then David and his entire army returned to Jerusalem." 2 Samuel 12:31 (NIV)
"David made the people of Rabbah tear down the city walls [a] with iron picks and axes, and then he put them to work making bricks. He did the same thing with all the other Ammonite cities. David went back to Jerusalem, and the people of Israel returned to their homes." 2 Samuel 12:31 (CEV)
Regarding 2 Samuel 12:31; 1 Chronicles 20:3 consider The Anchor Bible, which says: "David is setting up work crews of captives for the economic exploitation of the conquered territory, evidently standard practice for victorious kings.” Adam Clarke says: “He made people slaves, and employed them in sawing, making iron harrows, or mining . . . . And in hewing of wood, and making of brick. Sawing asunder, hacking, chipping, and hewing human beings, have no place in this text, no more than they had in David’s conduct towards the Ammonites."