17 But if your heart turns away, and you will not hear, but are drawn away to worship other gods and serve them, 18 I declare to you today, that you shall surely perish. You shall not live long in the land that you are going over the Jordan to enter and possess. 19 I call heaven and earth to witness against you today, that I have set before you life and death, blessing and curse. Therefore choose life, that you and your offspring may live, 20 loving the Lord your God, obeying his voice and holding fast to him, for he is your life and length of days, that you may dwell in the land that the Lord swore to your fathers, to Abraham, to Isaac, and to Jacob, to give them.
You WILL choose life IF God changes your WILL.
If God does not change your will then you will choose death. It is the nature of unregenerate man to reject God. It is like the story of the scorpion and the turtle.
The scorpion needs to cross the river and so he asks the turtle for a ride. The turtle says, "Do you think I am crazy? If I let you get on my back, you'll sting me."
"Don't worry," said the scorpion. "If I do that, we would both drown in the river."
So the turtle gives him a ride. Halfway across the river, the scorpion stings the turtle. And as the poison starts to work and the turtle and scorpion start to sink into the river together, the turtle says, "Why did you do it? Now we're both going to die."
The scorpion, in his last few breaths, says, "I couldn't help it. It's my nature."
Deu 31:27 For I know how rebellious and stubborn you are. Behold, even today while I am yet alive with you, you have been rebellious against the LORD. How much more after my death!
Deu 31:28 Assemble to me all the elders of your tribes and your officers, that I may speak these words in their ears and call heaven and earth to witness against them.
Deu 31:29 For I know that after my death you will surely act corruptly and turn aside from the way that I have commanded you. And in the days to come evil will befall you, because you will do what is evil in the sight of the LORD, provoking him to anger through the work of your hands."
Deuteronomy 31 is the reality (e.g you're rebellious, stubborn and evi).
Oddly enough our churches use to preach both messages. Now most of our churches seem only to want to preach Deut 30. (The good churches still preach both.)