What people are referred to as God's earthly people?
The nation of Israel is identified as God's earthly people. They are a special, called out, separated, covenant people whose promises are earthly. Their resurrection and eternal state will be earthly, not heavenly. They descend from Abraham as a distinctive race and nation.
Les explains that when Abraham was called out of Ur of the Chaldee, God separated him from the mainstream of humanity and promised that out of that one man would come a distinctive race and nation—Israel. Israel had it constantly drummed into their mindset that they were a special, called out, separated, covenant people of God, and all their promises are earthly. Therefore, they are referred to as God's earthly people. Les clarifies that while Old Testament saints went to paradise, the Jew's expectation in resurrection is earthly, not heavenly: when Jews experience resurrection as believers, they will be an earthly people, not a heavenly people. Even in their life in the flesh, all of Israel's promises were earthly, which is why many had tremendous wealth, as Abraham was a wealthy man.