David knows God. David knows he was anointed king. David is sure Saul is going to kill him. You can read in the Psalms about David’s despair and his hope. He goes up and down. Why isn’t he holding onto faith? Why don’t we?
David, who was unwilling to kill Saul, doesn’t trust God to protect him and so is going to rely on the Philistines for protection. How screwy does that sound?
God allows David to use the Philistines to protect David, but at what cost? David lives a lie the whole time he is there. He slaughters people, whole cities, with no indication God is sending him to battle and is lying about it. He’s telling the king of Gath that he’s bringing all this booty back from raiding the Israelites. He’s really killing other people groups to get their stuff and kills them off so they can’t tell on him.
You can’t live a lie without it affecting you. You can’t just slaughter people to keep them quiet without it affecting you.
Thinking he could get away with a big secret didn’t help David later in his life. His sins with Bathsheba and her husband, Uriah, were not the first and only discretions of David’s life. This was a lifestyle he chose and lived in. After he kills off Uriah (I’m jumping ahead in mentioning this), the rest of David’s life is messed up.
It wasn’t just one or two sins, even if really big sins; it was something in David’s heart that needed changing. He thought he could cover his sin. He thought that he was allowed to get away with some things if he could just keep people from knowing.
Our choice is never, “What can we get away with?” or “How much is okay?” It’s forsake all for Jesus. Forsake the world and the desires of the flesh and mind, even personal safety!
We forsake all for God. Let Him be your Savior!