The following words are credited to Leroy Lawson.
The words are spoken, but they aren’t enough. Some other expression is needed, something more tangible. That’s where the meal comes in, and the congregating of loved ones, and the expending of all the energy devoted to making the day different from other days. You need to do, not just say your thanks. You need a celebration, a representative activity, to make it work. You are seeking a way to give thanks together, to commune.
So in America, we celebrate Thanksgiving together in a kind of national communion. And in the church, we celebrate sacred Communion, which is always thanks-giving.
Thus like Jesus, before drinking from the cup and eating of the bread, we say thanks. We use plain words, but they are overlaid with centuries of gratitude.