Rejoice. Be glad. It is His gracious command, for the joy of the Lord is our strength (Nehemiah 8.10).
Pray. It is His generous promise, for whatever we ask the Father in the name of Jesus, He may give it to us (John 14.13; 15.16; 16.23).
Give thanks. It is His good precept, for His steadfast love endures forever (Psalm 118.29).
Gratitude is the habitual attitude when our humble and contrite heart experiences His grace and mercy. It is therefore the culture of the Kingdom of God. It is also a sign of maturity as a man/woman of God.
Gratitude begins as a belief, a belief that God the Father, the Son, and the Spirit is absolutely good to us personally and individually. Gratitude as a belief expresses itself in words and acts of thanksgiving to God. They, in turn, produce the habit (attitude) of gratitude.
It is good to give thanks to the LORD,
to sing praises to your name, O Most High;
to declare your steadfast love in the morning,
and your faithfulness by night,
to the music of the lute and the harp,
to the melody of the lyre.