Lord, Lord

This Christian life is not a walk of human strength; it requires far more than the ability any man or woman can offer. I mean specifically that we cannot bear the fruit of a Christian life by the exertion of our own vigor and determination. A life powered by sheer strength of will won't produce a truly fruitful walk. The humbling fact of the matter is that we cannot do anything eternally useful or significant without Him. ¹, ⁹

Paul wrote to the Corinthian church about this when he penned,

Therefore I want you to know that no one who is speaking by the Spirit of God says, “Jesus be cursed,” and no one can say, “Jesus is Lord,” except by the Holy Spirit. ²

Paul was not saying that it’s linguistically impossible for someone to utter those words without the help of the Holy Spirit; he was saying that our lives cannot back up those words without the Helper, the Spirit of liberty, the Spirit of Jesus. ³

When Paul instructs us on daily living after receiving Christ by writing,

Therefore, just as you received Christ Jesus as Lord, continue to live your lives in him, ⁴

he is not saying “try harder”; he is telling us to find our "all in all" in Jesus, the source of all that is good. He is telling us that our firm foundation is not in the philosophies of this world or a self-imposed asceticism, but rather in Christ, “in whom are hidden all the treasures of wisdom and knowledge.” ⁵

We live, not by our own might but by His Spirit, in the power of His might! ⁶, ⁷

We can pray and stay close to his heart, depending on him to infuse our efforts, the efforts we’ve committed to Him, with His life - 

so that you may live a life worthy of the Lord and please him in every way: bearing fruit in every good work, growing in the knowledge of God, ⁸

And even this comes from the Spirit. 

Isn’t it good to know that the end result of our labor in the Lord rests not in our striving or abilities, but in his ability? God has called us to His work, not ours, and He will provide all that is needed for the task at hand.

You can praise God for that!

References

¹ John 15:5 - "I am the vine; you are the branches. If you remain in me and I in you, you will bear much fruit; apart from me you can do nothing."

² 1 Corinthians 12:3

³ 2 Corinthians 3:17 - Now the Lord is the Spirit, and where the Spirit of the Lord is, there is freedom.

⁴ Colossians 2:6

⁵ Colossians 2:3

⁶ Zechariah 4:6 - Then he said to me, “This is the word of the Lord to Zerubbabel: Not by might, nor by power, but by my Spirit, says the Lord of hosts.

⁷ Ephesians 6:10 - Finally, be strong in the Lord and in the strength of his might.

⁸ Colossians 1:10

⁹ Jesus said that many would say to him on that day, "Lord, Lord ..." and list their qualifications for doing so. They prophesied, did mighty works, cast out demons. Their faith was in what they did and not who they knew. If they had known Jesus, they would have done all of these works, but out of relationship with him, being connected to Christ the head, and working in his power.