Many Christians know what they believe and they will not stray from that.

These folks are stable and well-grounded. Nothing budges them. They are strong and steady. They do not wander from the truth and faith they have been taught.

Unfortunately, too many of these people do not live in joyful thankfulness.

“Rooted and built up in him, and stablished in the faith, as ye have been taught, abounding therein with thanksgiving” (Colossians 2:7).

May I not miss the joy of living thankfully in Jesus.

And may I not be unstable and wimpy in the faith.

Surely you could add something...