Answer: Children of God should be overflowing with thankfulness, (verse 7).
MORE INFORMATION AND/OR OTHER SCRIPTURE REFERENCES:
If we are rooted in Christ, are built up in Christ and our faith is strengthened by the Truth of Jesus Christ--the Word of God--then we should definitely be overflowing with thankfulness.
Hebrews 12:28: "Therefore, since we are receiving a kingdom that cannot be shaken, let us be thankful, and so worship God acceptably with reverence and awe, for our ‘God is a consuming fire.'"