1 Samuel 27:2

Then the commanders of the Philistines said, “What are these Hebrews doing here?” And Achish said to the commanders of the Philistines, “Is this not David, the servant of Saul the king of Israel, who has been with me these days, or rather these years, and I have found no fault in him from the day he deserted to me to this day?”

So David went, he and the six hundred men who were with him, and they came to the brook Besor, where those left behind remained.

But it happened at the end of three years, that two of the slaves of Shimei ran away to Achish son of Maacah, king of Gath. And they told Shimei, saying, “Behold, your slaves are in Gath.”

Now these are the ones who came to David at Ziklag, while he was still restricted because of Saul the son of Kish; and they were among the mighty men who helped him in war.