This is why, for instance, there are numerous parallels between the Garden of Eden and the Land of Promise. Canaan was seen as a new Eden (and Israel was something of a new Adam). So it shouldn't surprise us to see that just as Adam was given a clear command by God in Eden, along with a reminder that disobedience to that command would bring about certain death, Israel also was given clear commands as they prepared to enter the Promised Land, as well as a reminder that certain death would be the result of their disobedience.
Notice the parallels, then, between Genesis 2:15-17 and Deuteronomy 30:15-18.
1) The presence of the LORD God - the covenant God
2) Clear command(s) - forbidden tree/the Mosaic law
3) A specific place or land - Eden/Canaan
4) A gracious warning - certain death is the result of disobedience
I have highlighted these parallels in italics below:
The LORD God took the man and put him in the garden of Eden to work it and keep it. And the LORD God commanded the man, saying, "You may surely eat of every tree of the garden, but of the tree of the knowledge of good and evil you shall not eat, for in the day that you eat of it you shall surely die." (Genesis 2:15-17)
"See, I have set before you today life and good, death and evil. If you obey the commandments of the LORD your God that I command you today, by loving the LORD your God, by walking in his ways, and by keeping his commandments and his statutes and his rules, then you shall live and multiply, and the LORD your God will bless you in the land that you are entering to take possession of it. But if your heart turns away, and you will not hear, but are drawn away to worship other gods and serve them, 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." (Deuteronomy 30:15-18)