I see being thankful or having thankfulness as two different things.
I know it sounds nit-picky, but I think the distinction is both useful and important for the discipline of thought-life management.
Giving thanks (aka thanksgiving) and being thankful are things I can do when I feel like it.
For example, I can choose to observe Thanksgiving on the fourth Thursday in November every year. When someone does something nice to me like give me a gift, I can be thankful in my heart and thank them with my mouth. These are nice and good things, but they are also responses to the actions of others.
Thankfulness, on the other hand, can be a premeditated decision.
It is a way of thinking that disciplines me to operate from a particular mindset.
The difference is between a response to good things when they happen in my life and a decision to live even in the darkest of times from a position of thankfulness.
This attitude will affect my life in profound ways I may not be able to see or feel at first.
Deciding to live out of thankfulness is the decision to live out of abundance and trust.
It is acknowledging that my life from the beginning is God’s special gift to me.
It is something he shares with me that is separate from everyone else.
It is unique and different from everyone else’s life and cannot be truly appreciated when, from my limited perspective, I attempt to compare it with the lives of others.
And this means I can make of it what I choose independent of the actions or choices of anyone or everyone else.
Finally, brothers, whatever is true, whatever is honorable, whatever is just, whatever is pure, whatever is lovely, whatever is commendable, if there is any excellence, if there is anything worthy of praise, think about these things.