And David rose up early in the morning, and left the sheep with a keeper, and took, and went, as Jesse had commanded him; and he came to the camp, as the host was going forth to the fight, and shouted for the battle.
Read Chapter 17
Caesarius of Arles
AD 542
As David came, he found the Jewish people located in the valley of Terebinth in order to fight against the Philistines, because Christ the true David was to come in order to lift up the human race from the valley of sins and tears. They stood in a valley facing the Philistines. They were in a valley, because the weight of their sins had pressed them down. However, they were standing but did not dare to fight against their adversaries. Why did they not dare to do so? Because David who typified Christ had not yet arrived. It is true, dearly beloved. Who was able to fight against the devil before Christ our Lord freed the human race from his power? Now the word David is interpreted as strong in hand; and what is stronger, brothers, than he who conquered the whole world, armed with a cross but not a sword? Furthermore, the children of Israel stood against their adversaries for forty days. Because of the four seasons and the four parts of the world, those forty days signify the present life...
Magala signifies, "the circle, or chariots. "The Arabs still place their waggons and baggage round the camp, or in a circle. (Calmet)
It may also be a proper name. (Menochius)