"The Lord is my strength, my shield from every danger.  I trust in Him with all my heart.  He helps me, and my heart is filled with joy.  I burst out in songs of thanksgiving!  ~ Psalms 28:7 (NLT)
David knew the power of thanksgiving. He understood that thanksgiving reflects a humble heart and is rooted in humble gratitude. He was genuinely grateful, and he trusted God to show up and deliver him.  For David, God meant life. No matter what our circumstances, we can always thank God for who He is and for delivering us from every evil darkness into every blessing of light. James 1:17 says, "every good and perfect gift is from above, and comes down from the Father of lights . . ."

Thanksgiving honors God and is a facet of praise; it is a biblical precept, and a key component of our Christian life. Philippians 4:6 instructs us to pray and petition God with thanksgiving, for thanksgiving is the antidote to worry. Paul reminds us in 1 Corinthians 10:16 that the Lord’s Table is where we drink of "the cup of thanksgiving," for we should ever be thankful of the sacrifice Jesus made for us at Calvary.

As Christians we of all people have reason to be thankful, and moreover we are called by God to express that gratitude.