Question: "What does it mean to be steadfast and unmovable?"
Answer: “Therefore, my beloved brothers, be steadfast, immovable, always abounding in the work of the Lord, knowing that in the Lord your labor is not in vain” (1 Corinthians 15:58, ESV). This verse concludes a chapter that details the future resurrection of our earthly bodies. Paul encouraged the Corinthian church to remain faithful to everything he had taught them. When we see the word therefore in Scripture, we should always back up to see why it is there: what is the “therefore” there for? The word usually indicates a summation of what was previously stated. In this case, Paul addresses those who had fallen away from his original teaching on the resurrection. They were embracing heresy and introducing destructive ideas contrary to the gospel. Paul restates the truth of Jesus’ death for sin and bodily resurrection and then exhorts them to remain firm in that teaching.
To be steadfast and unmovable is to be spiritually grounded. A steadfast person knows what he believes and cannot be “tossed back and forth by the waves, and blown here and there by every wind of teaching” (Ephesians 4:14). An unmovable person can hear false teaching, engage doubters, and defend truth without it shaking his own faith. In his other epistle to Corinth, Paul expresses his concern for this church: “I am afraid that just as Eve was deceived by the serpent's cunning, your minds may somehow be led astray from your sincere and pure devotion to Christ” (2 Corinthians 11:3). Even believers who had been personally taught by the apostle Paul were victims of deception. How much more vulnerable are we?
To remain steadfast and unmovable we have to know the Word of God. Second Timothy 2:15 says, “Be diligent to present yourself approved to God as a workman who does not need to be ashamed, accurately handling the word of truth” (NASB). To accurately handle the word of truth, we must not only read the Bible, but we must allow it to become part of us. Its truth should so penetrate our minds and hearts that it shapes our thinking and our actions. It should so fill our minds that we can detect error when we hear it. Satan uses Scripture for his own purposes, twisting it to sound as though it says something it doesn’t say (Luke 4:9–11). If we have not been diligent in our study and meditation on truth, we are vulnerable to error. The false religions of the world can be persuasive when they quote Bible verses to support their error. Even Christians can be duped by smooth-sounding heresy if they do not have a solid grounding in the “whole counsel of God” (Acts 20:27). It is God’s desire that we grow daily in our understanding of Him and His Word so that we will remain faithful to the end (John 8:31; 2 Peter 1:2; 3:18; 1 John 2:24).