Gratitude and thanksgiving are central themes in the teachings of the Apostle Paul. Many of his epistles begin with some form of thanks to the people whom he is addressing.
With his own thankfulness, Paul also instructs the Saints to be grateful, declaring that Christian should live lives of thanksgiving as an acknowledgment of God's goodness. Paul then goes on to say that in giving thanks to God, we find the pattern of how we should treat others.
Many of us praise the Lord every day in our prayers, thanking Him for the blessings which He has bestowed upon us. Too frequently, though, some of us (myself most especially) forget to give thanks to others in our lives. One day, my husband spent some time in making certain my car had a current registration sticker and papers. This required effort, as well as time.
I am ashamed to admit that I take such things for granted. I expect my car to have a current registration, expect it to be ready to drive whenever I need it.
This I know for sure: gratitude unexpressed is not gratitude at all.