“As you received Christ Jesus the Lord”: This refers to the act of accepting and believing in Jesus Christ as Lord. Receiving Christ is not merely an intellectual agreement with His teachings or an assent to some metaphysical premises; it's a wholehearted acceptance of Him as Lord and Savior. This is done by faith.
“So walk in him”: This is meant to encourage believers to continue living their lives in Christ. The term “walk” is often used in the Bible to refer to one’s lifestyle or manner of conduct. So, to “walk in him” means to live a life that is centered on Jesus, rooted in His teachings, and guided by His Spirit. [1]
The false teachings confronting Colossae placed an emphasis on deeds and personal sacrifice as pathways to gain favor with God. I think that we can acknowledge that actions play a significant role in the life of a Christian, as noted in 1 John 3:17-18. However, these actions are considered to be the outcomes of a saving faith, rather than its origin. [2]
I will note, some people may interpret “receiving Christ Jesus the Lord” as asking Jesus into your heart, however, this itself is a metaphorical expression. So, it’s not about saying a specific prayer, but about sincerely turning to Jesus in faith and committing to follow Him.
Now, the word “received” in Colossians 2:6 often refers to the reception of truth through teaching. [3] [4] This suggests that the Colossians had been taught the truth about Christ and had accepted it. The phrase “as you were instructed” in Colossians 2:7 further emphasizes this point. This indicates that the Colossians had been taught certain truths and were being encouraged to continue living according to those teachings.
So, in the context of Colossians 2:4-5 and Colossians 2:8, Paul was warning the Colossians against being deceived by persuasive arguments and human traditions. He was encouraging them to remain steadfast in the truth they had received and been instructed in.
While faith in Christ is certainly a crucial aspect of the Christian life, Paul’s emphasis in this passage seems to be on the importance of holding fast to the sound teaching that the Colossians had received and been instructed in
Conclusion: Colossians 2:6-7 is encouraging believers to continue living their lives in the same faith which they had been taught, through which they accepted Christ.