The Jews ordained, and took upon them, and upon their seed, and upon all such as joined themselves unto them, so as it should not fail, that they would keep these two days according to their writing, and according to their appointed time every year; And that these days should be remembered and kept throughout every generation, every family, every province, and every city; and that these days of Purim should not fail from among the Jews, nor the memorial of them perish from their seed.
Esther 9:27-28
When God used Mordecai and Esther to foil the wicked plot of Haman to destroy the Jewish people throughout the Persian Empire, they rejoiced. It is only right and proper that we give thanks for what God does for us. But that was not all they did. They also established a new celebration, the Feast of Purim, which is still observed today by Jewish people around the world. In synagogues the story of Esther will be read. (A relatively-modern, dating back to the thirteenth century, practice is that children at these celebrations are given noisemakers to drown out the name of Haman every time it is read.) Mordecai established this observance so that the people would not forget what God had done for them in years to come.
Every child of God has received blessings far beyond what we deserve. Salvation alone would be enough to merit a lifetime and then an eternity of gratitude. But God gives us far more than that because of His gracious and loving character. Paul asked, “He that spared not his own Son, but delivered him up for us all, how shall he not with him also freely give us all things?” (Romans 8:32). It is our responsibility to avoid the trap of thinking somehow we deserve God's blessings. That attitude destroys gratitude and praise very quickly. Instead, we should be reminding ourselves constantly of what God has done, and praising Him to others. “Then was our mouth filled with laughter, and our tongue with singing: then said they among the heathen, The LORD hath done great things for them” (Psalm 126:2).