But we see in Colossians 3:15 Paul instructs the Colossian Christians that they were to have a "thankful heart." As Christians what does this mean? Well, when you look at the full context has a much fuller meaning than mere thankfulness.
Colossians has many references to thankfulness, but the word Paul uses here is unique, it is not used anywhere else in the New Testament. Also, in full context, it is directly linked to the exhortation to allow "the peace of Christ, to which you were also called in one body, rule your hearts. And be thankful" (Colossians 3:15).
The combination of "peace" and "thankfulness" here is quite logical. When you lack peace, you will also lack thankfulness, and more often than not the lack of peace comes from a dissatisfaction with things as they are or from other selfish motivations. On the converse when one is thankful, having come to the realization that all things are provided in Christ we find real peace.
When we come to rest fully in Christ. When we trust in Him and embrace His Word of Truth. That is when we find the true peace that passes all understanding. That is when we face the storms of this life, and we can sing songs of praise to the one who saved our eternal soul.
"Therefore, as God’s chosen ones, holy and dearly loved, put on compassion, kindness, humility, gentleness, and patience, bearing with one another and forgiving one another if anyone has a grievance against another. Just as the Lord has forgiven you, so you are also to forgive. Above all, put on love, which is the perfect bond of unity. And let the peace of Christ, to which you were also called in one body, rule your hearts. And be thankful. Let the word of Christ dwell richly among you, in all wisdom teaching and admonishing one another through psalms, hymns, and spiritual songs, singing to God with gratitude in your hearts. And whatever you do, in word or in deed, do everything in the name of the Lord Jesus, giving thanks to God the Father through him." - (Colossians 3:12-17 CSB)
See ya Sunday!