Lucado writes of "faith wounds," which are different from flesh wounds. We all have them - by their very nature you can't see them. I won't reveal mine in this forum, which is too public for that level of honesty. But, needless to say my faith wounds manifest themselves in my flesh.
At this point in the "story" (is it appropriate to call it a "story?") David has lost his focus on God. He is despondent and now believes that Saul is going to kill him. So David leaves and goes to the Philistine country. Saul gives up the hunt for David. But, David is hiding out with the enemy. He feels relief - but only a temporary relief.
David sells out - he strikes a deal with Achish, the king of Gath, asking for a village. In return, David promises to serve Achish. So, Achish grants David a village, Ziklag, and asks that David kill his own people. David agrees to do this. However, instead of killing his own people, David raids other villages, killing them and taking their property, for sixteen months.
Then the Philistines attacked King Saul. While David and his men were away, David's village Ziklag was burned to the ground and all the wives and children were kidnapped. David's men are devastated - they gather stones to hurl at David.
All of this started because David made a bad decision and decided to move to the land of the Philistines, his enemy. Because David has taken his focus off of God. Lucado writes "Slumps: the petri dish for bad decisions, the incubator for wrong turns, the assembly line of regretful moves." How true this is - I know when I look back at the failures in my life. Most, if not all, of them started with me making one bad decision. It is easy to see now, in hindsight. But it would be better to more carefully analyze why I am making certain decisions. Have I taken my focus off of God? Am I making this decision in the midst of faith wounds, while in a slump?