What does Psalm 16:6 mean?

When Israel conquered Canaan, the Lord assigned each tribe a portion of the land except Levi, whose inheritance was the Lord (Joshua 13—21). Each inherited section of Canaan was carefully allocated and marked. Measuring lines specified the land each tribe, clan, and family owned. Each lot received a landmark that was permanent. Deuteronomy 19:14 prohibited the people from moving the landmarks. This verse commands: "You shall not move your neighbor's landmark, which the men of old have set, in the inheritance that you will hold in the land that the LORD your God is giving you to possess."

Continuing his celebration from the prior verse (Psalm 16:5), David rejoices that his inheritance had fallen in pleasant places. He views his inheritance as a beautiful gift from the Lord. Believers, too, have a beautiful inheritance as a gift from the Lord. Ephesians 1:11 explains, "In him we have obtained an inheritance, having been predestined according to the purpose of him who works all things according to the counsel of his will."