But you must understand something that includes that, an overall function that we have in this world: gratitude. We see this in Rashi’s explanation on this mishnah, which he says in Berachos (63a): “Accustom yourself to saying His blessings in this world in order that you should be practiced in them for the World to Come.” All you sad-faced people, perk up and pay attention. Accustom yourself to saying to Hashem in this world: “Baruch Atah,” “Thank You” and “Thank You” and “Thank You.” Instead of being morose, instead of being sad, you have to be happy in this world; you have to thank Hashem continually. There is so much that He is giving us — a veritable smorgasbord! There are so many “knishes” — we will soon see that the knishes in this world that I am talking about are a different kind, and better than the ones served by the caterers. There are so many good things they are serving us in the lobby here that we have to continually say with the fullest of hearts: “Thank You,” “Baruch Atah,” “Thank You,” “Baruch Atah.” The Gemara (Sanhedrin 91b) says: “All who sing shirah (song) in this world merit to sing it in the World to Come.” The emphasis is on song — not prose. When a man says, “Things are good,” that is prose. But suppose you get a call from the lottery commission that you just won the jackpot and then your wife asks you, “What is it?” You won’t speak prose to her. You will speak in poetry! You will speak in lyric verse! You might even dance, too. When you sing your song in this world, don’t mumble it, saying, “Baruch Atah Hashem.” As an old mashgiach used to say, “You boys, when you make a berachah, you would not even open up your mouths if not for the fact that you’re eating a piece of bread! When you say a berachah, say it like you mean it! You have to thank Hakadosh Baruch Hu from the bottom of your heart.”

Miller, Rabbi Avigdor. Rav Avigdor Miller on Emunah and Bitachon . The Judaica Press, Inc.. Kindle Edition.