In Psalm 100, the psalmist reminds us to "Enter his gates with Thanksgiving in our hearts."
In 1 Thessalonians 5:18, Paul says, "In everything give thanks."
Thankfulness helps us to see life in a brighter light. We often focus on our problems and what we "don't" have. If we were to make a list of all that we do have for which we should be thankful, life would appear a lot better to us.
As we think about Thanksgiving, the name of the holiday is a message in itself. If we are truly thankful, we'll want to give: giving thanks leads to other forms of giving. Jesus reminds us, "Freely you have received, freely give." (Matthew 10:8) The woman who brought the alabaster jar of perfume, poured it on Jesus feet after she had washed His feet with her hair, brought a very valuable gift. She did this because she was so thankful for Jesus' love and forgiveness. (Luke 7:37-38; Luke 7:47-50)
We have so many reasons to be thankful. We have been so blessed. Our thankfulness for these blessings should make us want to give.
Then it is easy to give with thanks.
My son went with me on a mission trip to Guatemala when he was 8 years old. I had given him some spending money for souvenirs. When he saw the poor children and realized how little they had compared to what he had, he walked up to one of the children and gave the child his spending money. If we are thankful for what we have, we should want to help out those who are in need and keep in circulation the Lord's blessings. I think it is a way to give back to the Lord. Jesus tells us that when we do it for others, you are doing it unto Me.
When we realize that God is the source of all of our blessings — financial, physical, and spiritual — then it is easy to give with thanks. If we don't realize that He is the source, we may try to hold on to it in fear that we'll lose it. I hope that this Thanksgiving and Christmas we'll be both thankful and giving.