Therefore, as you received Christ Jesus the Lord, so walk in him,  rooted and built up in him and established in the faith, just as you were taught, abounding in thanksgiving.
 See to it that no one takes you captive by philosophy and empty deceit, according to human tradition, according to the elemental spirits of the world, and not according to Christ.
This is a word of warning to Christians who were rooted in Christ Jesus, to be cautious of being deceived by false teaching leading away from the Truth of Him. While they were well grounded and built up in Him, they were nonetheless susceptible to false teaching.
If we were to be taken physically captive by someone, we would be held against our will. It may be very hard to escape, We would no longer have freedom. We would be taken away from the things we have, from the things we have been given, and from those we love.
If we were to be taken mentally captive by false teaching, lies deviating from the Truth of the Word, according to the goings on of this world, we would be leaving behind the Truth given to us with Christ Jesus. We would be wrecking the foundation we have in Him, established in faith. We would be taken captive from the One who matters the most.
As Christians we need to be well rooted in the Truth of Jesus. So much so that we discern when others are trying to get us to sway from that Truth. We need to stay firm in our faith, using Jesus as our compass, knowing that everything should lead back to Him.
Lord thank You for Your Truth. Truth that guides me to You in my thoughts and my actions. Lord continue to build me up and help me sink stronger and stronger roots in the Truth of Your Word. Jesus help me be more like You and give me discernment when outside forces attempt to deceive me away from You. Amen.