It is jarring to read of David’s deceit. The Bible is clear that God is truth (John 14:6; 1 John 5:20) and he does not lie (Titus 1:2; Hebrews 6:18). Truth comes from God (Psalm 43:3) and his word is truth (John 17:17). Still, the Lord can and does sometimes use deception in order to judge his enemies (see 1 Samuel 17:14; 1 Kings 22:19–23; 2 Kings 7:6–7; Jeremiah 4:10; 2 Thessalonians 2:11–12).1 In a wartime situation, it appears as if there is room for deception (withholding certain information) when it comes to dealing with an enemy (see Joshua 8:2). This is what David did to Achish and even then, we should be careful to say that he told a lie. He did go raiding in the Negeb of Judah, Jerahmeelites, and the Kenites, but he raided the raiders and not the people who lived there.
10 When Achish asked, “Where have you made a raid today?” David would say, “Against the Negeb of Judah,” or, “Against the Negeb of the Jerahmeelites,” or, “Against the Negeb of the Kenites.”