Roman philosopher Quintilian said, “A liar should have a good memory.” The actions recorded in chapters 16-17 bring to the surface a basic Christian ethics question. Is it ever okay to lie? A great deal of David’s survival depended on deception. For example, David sends Hushai back to Jerusalem for the express purpose of spying on Absalom’s plans – plans that included Hushai deceptively posing as loyal to Absalom’s causes. Hushai provides counsel to Absalom that intentionally leads him to a poor strategic decision in his pursuit of David. The priests Zadok & Abiathar involve themselves in espionage in order to advise David of Absalom’s intent to attack.
Is lying always a sin? Or can deception be a godly action, if used for the greater good? This and questions like it, have been debated for centuries and will continue. For some thought provoking discussion on the ethics of lying, see this link from the BBC: http://www.bbc.co.uk/ethics/lying/lying_1.shtml.