Started in Christ
Put, for, as God's chosen, holy and beloved, with compassion, of benignity, of humility, of gentleness, patience; bearing with one another, and forgiving one another if anyone has a complaint against another. For as Christ forgave, so also do ye. And above all these things put on love, which is the perfect bond. And the peace of God rule in your hearts, to the which also ye are called in one body; And be thankful. The word of Christ dwell in you richly, teaching and admonishing one another in all wisdom, singing with grace in your hearts to God in psalms and hymns and spiritual songs. Colossians 3:12-16
The concept of gratitude which contains this passage is much more than a simple "thank God for ...". The word gratitude to take action related in any way. According to the Apostle Paul is speaking to the brethren at Colosse, Christians have a way to be distinguished and specifically mentions the need to not try to impress with attitudes and customs that only deal with appearances. Then, begins to talk about the true characteristics that identify us. Finally, Paul mentions being thankful all the time as something special that sets everyone who lives in Christ.
As Paul teaches in 2 Corinthians 5:17 and Ephesians 2:1, God gave us life in Christ and makes us new creatures to enable us to start living that life in Him. It requires effort on the part of each power dressing as God's chosen. In fact the basis of life as a new creature is in recognizing what our own identity and the key is to search out to enjoy eternal life(John 5:39 and 17:3). This allows us to live and valuing each other as to who we are and what we do. Only in this way we can thank God for his grace and mercy. Be grateful!