Deuteronomy 11

“Therefore you shall keep every commandment which I command you today, that you may be strong, and go in and possess the land which you cross over to possess,  and that you may prolong your days in the land which the Lord swore to give your fathers, to them and their descendants, ‘a land flowing with milk and honey.’" vv.8-9

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The word 'land' occurs a dozen times in this chapter.  It is referring to the land of Canaan that Israel was about to go in and possess.  It is not only the Promised Land but "it was also the "land of promises" because that land God would fulfill many of the promises relating to His great gift of salvation for the whole world.  The land of Israel would be the state on which the great drama of redemption would be enacted.  There the Savior would be born and live and there he would die for the sins of the world" (Be Equipped, Warren Wiersbe).  
They were to keep God's commandments, not as some burdensome task as most people today look on the law of Moses but to them it was a delight and for their safety.  Keeping the Lord's commands made them strong (v.8).  Sin we know weakens the body and mind, but living according to God's plan gave them strength as to health in body and courageous in mind.  When Moses says that it would 'prolong your days' this didn't necessarily mean they would live for a really long time, although it was promised that they would go in and possess it, but also that each day would be full of abundance. How have you seen your days richer when you walk in God's ways? 
We can't claim God's promises just by hanging up scripture on our walls or wearing a cross around our neck which is much easier and the danger of most Christians today, but a lot harder to hide His word in our heart that we might not sin against Him (Psalm 119:11).