1 Chronicles 16:34
O give thanks unto the LORD; for he is good; for his mercy endureth for ever.
The word picture behind the phrase "O give thanks" is: a deed done that opens the door of humility, selflessness and self denial to the breath of God, divine revelation and His light.
On the site in Bethlehem, that is believed to be the birthplace of Yeshua, stands the Church of the Nativity. You enter the Church of the Nativity via what is known as the door of humility. You can see from the above picture why it bears that name.
When we see this link between thanks and the birth of Yeshua we realise that to give thanks is to focus on the goodness of Yahweh.
1 John 4:9 In this was manifested the love of God toward us, because God sent his only begotten Son into the world, that we might live through him.
Also, it highlights to us the fact that thanks is not just words but rather actions. Perhaps this will help bring new light to the following scripture:
1 Thessalonians 5:16-18 Rejoice always, pray without ceasing, in everything give thanks; for this is the will of God in Christ Jesus for you.