What was Adam's position as federal head of the human race?
Adam was the federal head of the human race, given dominion over everything God created. That dominion meant it was his to rule and reign over all creation. Despite having all power and ideal circumstances, he fell when Satan tempted him.
Les explains that Adam was the federal head of the human race and was given dominion over everything God created; it was his to rule and reign over. That is what dominion meant. Adam had all that power at his disposal, under beautiful circumstances, with nothing to be desired and everything there for him, yet Satan came with one little temptation and Adam fell. Les contrasts this with Christ, who came in His earthly ministry not yet as the royal king but more as a servant, lowly, riding upon the foal of an ass, and epitomized servanthood by washing the disciples' feet.