'Intervening' in the Bible

Then Gideon sent messengers throughout the hill country of [the tribe of] Ephraim, saying, “Come down against the Midianites and take [control of] the waters before them [thereby cutting off the Midianites], as far as Beth-barah and the Jordan [River].” So all the men of Ephraim were assembled together and they took control of the waters, as far as Beth-barah and the Jordan.