Obey, read, meditate (pray), do as it says and you will be successful (1:6-9). The Jordan river stops flowing (chapters 3 & 4). The walls of Jericho fall down (5:13-6:27). Disobedience is not tolerated (chapter 7). Chapter 12 lists all of the kings who the Israelites defeated. But there were still large areas of land to be taken over (13:1-5). Division of the land (13:6-21:45).
"...be careful to obey all that is written...without turning aside to the right or to the left...hold fast to the Lord your God...if you turn away...you (will) perish from this good land..." (23:6-13). Chapter 24 is a review, note especially verses 20-24.