1 Chronicles 12:19

And of Manasseh there have fallen unto David in his coming with the Philistines against Israel to battle -- and they helped them not, for by counsel the princes of the Philistines sent him away, saying, 'With our heads he doth fall unto his master Saul.' --

1 Samuel 29:2-9

and the princes of the Philistines are passing on by hundreds, and by thousands, and David and his men are passing on in the rear with Achish.

Treasury of Scripture Knowledge

Summary

And there fell some of Manasseh to David, when he came with the Philistines against Saul to battle: but they helped them not: for the lords of the Philistines upon advisement sent him away, saying, He will fall to his master Saul to the jeopardy of our heads.

When he came

Bible References

When he came

1 Samuel 29:2
and the princes of the Philistines are passing on by hundreds, and by thousands, and David and his men are passing on in the rear with Achish.