Giving thanks causes you to be reminded of what you are thankful for and this gives you a fresh appreciation of all the blessings in your life. This appreciation stokes the flame of joy unspeakable to burn afresh in your heart.

As the old hymn says:

Count your many blessings

Name them one by one

And it will surprise you what the Lord has done!

Bless the Lord, O my soul,and forget not all his benefits:

Who forgiveth all thine iniquities; who healeth all thy diseases;

Who redeemeth thy life from destruction; who crowneth thee with lovingkindness and tender mercies; Who satisfieth thy mouth with good things. Psalm 103:2