Ephesians 4:17

The "therefore" in this verse is coordinate with the one in Ephesians 4:1. Here we have more instruction concerning walking worthily. Paul’s exhortation that follows repeats Jesus’ teaching on the importance of holiness. Christians should not conduct themselves as Gentiles who do not know the Lord. Those unbelievers do not typically have a worthy aim or goal in life, the idea behind "the futility of their mind [thinking]."

"What is immediately noteworthy is the apostle’s emphasis on the intellectual factor in everybody’s way of life [cf. Romans 12:2]. . . . Scripture bears an unwavering testimony to the power of ignorance and error to corrupt, and the power of truth to liberate, ennoble and refine." [Note: Stott, p. 175.]