The central message of this sermon is that God's freedom to bestow or withhold mercy is an inherent right based on His sovereign nature, and it is not bound by human expectation or fairness. This concept is developed through a biblical interpretation of Romans 9:14-18, where Paul explains that God's mercy is not granted due to human deservingness or effort, but rather solely because He chooses to show it. The sermon also explores the idea of "hardening" in Exodus, where God reinforces Pharaoh's will to resist Him, enabling him to become more fully what he desires to be, ultimately for the purpose of displaying His power and glory. This theological concept advances the belief that God is sovereign and just, and that His actions are not arbitrary or unfair. The takeaway for listeners is to understand that God's rights and freedoms are intrinsic to His nature, and that human expectations of fairness or deservingness do not apply to Him.