We have to think to become thankful.
We have to think to be aware of the things done for us; the cost and sacrifice involved in the doing of those things.
We have to think to become appreciative and grateful.
We have to think to express our appreciation and gratitude.
That’s why the story of David receiving the drink of water from the well in Bethlehem is such a strong story of thanksgiving. (2 Samuel 23:13-17)