Chapter 29: Obedience=Blessings, Disobedience= Cursing
Israel makes a covenant with the Lord that if they are obedient they will be blessed and if they are disobedient they shall be cursed.
In verse 6, it states that they knew God by not eating or drinking wine. Two ways to take this, fasting (by abstaining from food and water, helps you to feel the spirit), or that not drinking alcohol (keeping your body a temple and treating it that way, helps you to see God, sober.)
I personally believe that it is a combination of both, fasting and abstaining from Alcohol. Moses also says that they who disobey the Lord will be cursed, like the cursing of the book (of Deuteronomy). In verse 29 it talks about the secrets of the Lord can be revealed. How can you have revelation if the Canon of the Bible is closed? You can’t. That is why the LDS church believes that there is an open Canon.
Chapter 30: Blessings and Curses
When Israel scatters, the Lord promises to gather them again. The Lord tells the people that he will remember the covenant that he has made with them. Moses tells the people that they can either live or die, but they must obey the commandments if they want blessings. OR they can be cursed with all manner of curses.
VERSE 6-7, Love God with all your heart and mind, and he shall curse your enemies.
VERSE 14-17, Listen to God and do what he wants or you WILL fall away!