Definition and Context:
Territorial conquest in the biblical context refers to the acquisition of land through military means, often under divine directive. This concept is prominently featured in the Old Testament, where the Israelites, under God's command, engage in battles to take possession of the land promised to them by God. The conquest of Canaan is the most significant example of territorial conquest in the Bible.

Biblical Instances:

1. The Conquest of Canaan:
The most notable instance of territorial conquest is the Israelites' conquest of Canaan under the leadership of Joshua. After the death of Moses, Joshua was appointed to lead the Israelites into the Promised Land. The conquest began with the miraculous crossing of the Jordan River and the fall of Jericho. Joshua 1:2-3 states, "Moses My servant is dead. Now therefore arise, you and all these people, and cross over the Jordan into the land that I am giving to the children of Israel. I have given you every place where the sole of your foot will tread, just as I promised to Moses."

2. Divine Command and Guidance:
The conquest was not merely a human endeavor but was carried out under divine command and guidance. God instructed the Israelites to drive out the inhabitants of the land and to destroy their altars and idols to prevent the Israelites from being led astray. In Deuteronomy 7:1-2 , God commands, "When the LORD your God brings you into the land you are entering to possess, and He drives out before you many nations... you must devote them to complete destruction. Make no treaty with them and show them no mercy."

3. The Role of Faith and Obedience:
The success of the territorial conquest was contingent upon the Israelites' faith and obedience to God's commands. The fall of Jericho, as described in Joshua 6, exemplifies the importance of following divine instructions. The Israelites marched around the city for seven days as God commanded, and on the seventh day, the walls of Jericho fell after the people shouted and the priests blew the trumpets.

4. Challenges and Failures:
The conquest was not without challenges and failures. The sin of Achan, who took forbidden items from Jericho, led to Israel's initial defeat at Ai (Joshua 7). This incident underscores the necessity of holiness and obedience in achieving God's promises. Once the sin was addressed, God granted victory over Ai.

5. The Allotment of the Land:
After the conquest, the land was divided among the twelve tribes of Israel. This allotment was done by casting lots, as described in Joshua 14-19, ensuring that each tribe received its inheritance according to God's promise.

6. Theological Significance:
Territorial conquest in the Bible is deeply theological, symbolizing God's faithfulness to His covenant promises. It also serves as a foreshadowing of the ultimate victory and rest that believers find in Christ. Hebrews 4:8-9 reflects on this, stating, "For if Joshua had given them rest, God would not have spoken later about another day. There remains, then, a Sabbath rest for the people of God."

Moral and Ethical Considerations:
The concept of territorial conquest raises moral and ethical questions, particularly regarding the destruction of entire populations. From a biblical perspective, these actions are understood within the framework of divine justice and the eradication of idolatry and sin. The Canaanites' practices were seen as abominable, and their destruction was a means of purifying the land for God's people.

Conclusion:
While the concept of territorial conquest is complex, it is integral to understanding the narrative of the Israelites and God's unfolding plan of redemption. The biblical accounts emphasize God's sovereignty, the importance of faith and obedience, and the fulfillment of divine promises.