The central message of this sermon is that true righteousness is not about external actions, but about internal motivations. Jesus assumes that his listeners are already doing good works, but warns them against seeking the wrong reward - the praise and approval of others - instead of the reward from God. The speaker argues that hypocrisy arises when we seek to be seen or noticed by others for our good deeds, rather than genuinely desiring to please God. The takeaway is that our motivation matters more than our actions, and that if we focus on pleasing others rather than God, we risk falling into the trap of hypocrisy.