The book of Judges is linked to the book of Joshua. Although the book begins with the words, “After the death of Joshua…” (Jg 1:1) there is evidence that some of the happenings are narrated before Joshua’s death. For example Judges 2:6 reads, “When Joshua sent the people away…” It would then appear that chapters 1 through 3 serve an introduction for the rest of the book; which serves as a chronilogical acount of the events of 12 Judges. (not including Deborah)
Previously you read that God required that the peoples that the Israelites conquered had to be driven from the land. Consistently there were warnings about adopting the false worship of the Canaanites and others.
Throughout the OT the Israelites go up against superior foes, but as long as the Israelites display faith, and follow divine direction, they consistently prevail.
For example, look at **Exodus 23:32, 33 ** , * "32 You are not to conclude a covenant with them or their gods. 33 They should not dwell in your land, that they may not cause you to sin against me. In case you should serve their gods, it would become a snare to you.” *
But what actually happened? Look at Jg 2:2,3 as a comparison, *"2 And for YOUR part, YOU must not conclude a covenant with the inhabitants of this land. Their altars YOU should pull down.’ But YOU have not listened to my voice. Why have YOU done this? 3 So I, in turn, have said, ‘I shall not drive them away from before YOU, and they must become snares to YOU, and their gods will serve as a lure to YOU.’” * (highlights mine)
It’s clear that the Israelites did not follow the direction they were given, and as result did not enjoy God’s support. Also look at Nu 33:55 which says, "55 “‘If, though, YOU will not drive the inhabitants of the land away from before YOU, then those whom YOU leave of them will certainly become as pricks in YOUR eyes and as thorns in YOUR sides, and they will indeed harass YOU on the land in which YOU will be dwelling. ** (Also see Exodus 34:11-17 and De 7:2-5)**
If you look at those cites in Exodus, Numbers, and Deuteronomy the consistent message to the Israelites was to either wipe out, or drive out, the peoples they beat in battle. They were NOT to keep them around, inter-marry, conclude any agreements or fall prey to their religious influences.
Did they follow the program?
Look at Joshua 16:10,* “10 And they did not drive away the Ca´naan·ites who were dwelling in Ge´zer, and the Ca´naan·ites continue dwelling in among E´phra·im down to this day and came to be subject to slavish forced labor.”* or Joshua 17:12, 13, “12 And the sons of Ma·nas´seh did not prove able to take possession of these cities, but the Ca´naan·ites persisted in dwelling in this land. 13 And it turned out that when the sons of Israel had grown strong, they went putting the Ca´naan·ites at forced labor, and they did not dispossess them entirely.”
Did the Israelites have a basis to believe they could prevail, even when outnumbered? (iron scythes or not…) Look at De 20:1, "20 “In case you go out to the battle against your enemies and you actually see horses and war chariots, a people more numerous than you, you must not be afraid of them; for God is with you, who brought you up out of the land of Egypt. "
Yep.
But as shown, not just in this case, but throughout their history, the Israelites would fall prey to foreign and essentially turn their back on the direction they were given. Consistently the Israelites prevailed against superior foes. When they did not, it’s because they lost god’s favoe due to their disobedience and/or lack of faith. (see Jg 4:3 & Ps 106:34)