'Simplicity' in the Bible

And thou -- if thou dost walk before Me as David thy father walked, in simplicity of heart, and in uprightness, to do according to all that I have commanded thee -- My statutes and My judgments thou dost keep --

And a man hath drawn with a bow, in his simplicity, and smiteth the king of Israel between the joinings and the coat of mail, and he saith to his charioteer, 'Turn thy hand, and take me out from the camp, for I have become sick.'