1 Samuel 29:4

And the princes of the Philistines were wroth with him
With Achish, for giving such a character of David, and taking his part, in order to detain him, if possible:

and the princes of the Philistines said unto him, make this fellow
return;
they speak of him with contempt, and insist on it that Achish order him to turn back, and go no further with them:

that he may go again to his place which thou hast appointed him;
to Ziklag, the place that Achish had given him for his residence, ( 1 Samuel 27:6 ) ; they did not desire to have him sent to his own country, and to Saul, since should a reconciliation be made between them, he would be of great service to Saul against them:

and let him not go down with us to battle;
into the valley of Jezreel, where the Israelites had pitched:

lest in the battle he be an adversary to us:
and fall upon them behind, being in the rear, while they were engaging in the front with Israel:

for wherewith should he reconcile himself unto his master?
to Saul he had offended, and fled from:

[should it] not [be] with the heads of these men?
the Philistines; or unless by the heads of these men ^F13; he had no other way of making his peace with his master but by cutting off the heads of the Philistines; and therefore he was a dangerous man to take with them into the battle.