1 Samuel 23:20-21 ASV

Earlier in this chapter, David and God communicate back and forth, with God giving David direction and answers to some of his questions. So, we know God is helping David. These two verses interest me, because they show that Saul assumes God is on his side, too. Don't we all?
So how do we know whose "side" God is on? I see a couple things in this passage that give me clues. First, David goes to God in prayer. He asks him questions and expects answers. He doesn't necessarily follow God's instructions the first time, but he does ask. He also acts on the information God gives him with his own common sense. For example, God tells David that Saul is coming for him and that the citizens will surrender him. God doesn't tell David to flee. David just acts on the information. I think this is important for us to remember. When we have information or guidance from God, we have a responsibility to move with it. We do not have to have clear guidance about every baby step; that's why God gave us minds.
So, I see David engaging God in conversation and then acting. Alternately, I see Saul just acting and not engaging God in dialogue. Saul goes down the dangerous road of assuming. In this case, he assumes God is on his side when he announces God's blessing on the Ziphites for being concerned about him.
Before I villainize Saul, I must remember that I assume God is on my "side", too. How important it is for us to remember that God is the God of all people, and God may very well be communicating with my adversary more than he and I are communicating.