1 Samuel 27:11-12 [David] did not leave a man or woman alive to be brought to Gath, for he thought, “They might inform on us and say, ‘This is what David did.’” And such was his practice as long as he lived in Philistine territory. Achish trusted David and said to himself, “He has become so odious to his people, the Israelites, that he will be my servant for ever.”
Sadly, life in a fallen world is never going to be simple and straightforward. God, the Creator, has given us clear rules that will enable us to live together in peace and harmony, but our sin-affected hearts are not content with these rules, and we want to make up our own code of ethics to suit our self-orientated needs and desires … and this is what makes it complicated for everyone!
To help us, God summarised the rules into 10, easy to understand commandments that he inscribed for Moses on tablets of stone on Mt Sinai. This ‘Law’ became central to David’s worldview, and something which he saw to be “perfect, reviving the soul … trustworthy, making wise the simple … right, giving joy to the heart … radiant, giving light to the eyes” (Psalm 19:7-8), and therefore something in which he ‘delighted’ and on which he ‘meditated day and night.’ (Psalm 1:2).
But the struggle we have with today’s verses is that we find David blatantly going against the 7th of the ’10 Commandments’! But, this was a necessary part of of his need to escape from King Saul’s determination to break the 6th Commandment by killing him! And his lying to, and deception of, the Philistine, along with his annihilation of them, was part of God’s punishment of them for their persistent disregard for the implications of the 1st and 2nd Commandments (cf Romans 1:18-20), just to name two!
Perhaps we see a more modern equivalent of all this in the way some courageous German Christians told lies to Hitler’s henchmen to protect the Jews. Yes, in a fallen world, we often find that living consistently with God’s rules requires us to make decisions that are not strictly ‘right’, but are a case of choosing between the lesser of two evils.