A key promise in the book of Joshua is that as God's people advanced, so he would destroy their enemies. As they obeyed him, moving forward and taking courageous steps of faith, he would make their enemies retreat and he would drive them away. True to his word, God told them just before the death of Joshua, "As you advanced, I threw them into panic … and I destroyed them." God's promises never fail.

While Joshua's generation remained alive, Israel served the Lord; but in the first chapter of Judges the words "did not drive out" or "were unable to drive out" occur many times. The tribes of Judah, Benjamin, Manasseh, Ephraim, Zebulun, Asher, Naphtali and Dan are specifically mentioned as not driving them out. They ended up "living with the local Canaanites".

God then said to them: "I will never break my covenant with you. You must not make any covenant with the people who live in this land. You must tear down their altars. But you have not done what I told you. You have done just the opposite! So I tell you now that I will not drive these people out as you advance. They will be your enemies, and you will be trapped by the worship of their gods" (Jdg. 2:1-3).

"Then the people of Israel sinned against the Lord and began to serve the Baals. They stopped worshiping the Lord, the God of their ancestors, the God who had brought them out of Egypt, and they began to worship other gods, the gods of the peoples around them. They bowed down to them and made the Lord angry … The people of Israel settled down among the Canaanites, the Hittites, the Amorites, the Perizzites, the Hivites, and the Jebusites. They intermarried with them and worshiped their gods" (Jdg. 2:11-12; 3:5-6).

Instead of completing the conquest that Joshua had largely accomplished, the very next generation either failed to guard their hearts or revealed they had never truly yielded their hearts to God and became unfaithful to him. A lack of heart-commitment led to fear, disobedience, compromise, unfaithfulness, idolatry and being absorbed into the very culture they had been sent to destroy. It is the same lesson we have seen before: only yield your heart to God and do so completely; once yielded choose to guard it and you will find God guarding it too. And keep advancing; pressing on to know him more.