7 “Therefore do not become partners with them; 8 for at one time you were darkness, but now you are light in the Lord. Walk as children of light 9 (for the fruit of light is found in all that is good and right and true), 10 and try to discern what is pleasing to the Lord.” (Ephesians 5:7–10 (ESV)
Believers in Christ are to be imitators of God in their life and lifestyle (Ephesians 5:1). We are also to not be sharers or joined with those who rebelliously live in sin (Ephesians 5:3-7). The reason for this is because Christians are light in the Lord (Ephesians 5:8; Matthew 5:13-16). Therefore, God commands us to live as children solely belonging to the light of God.
What does living in the reflected holy light of God look like in our everyday world? The Apostle Paul provides us with some answers.
For the fruit of light is found in all that is good and right and true. Fruit (καρπός; karpos) is used here metaphorically to signify the deeds and behavior of the believer in Christ. This metaphor is found throughout the Scriptures (Isaiah 5:1-7; John 15:1-11; Galatians 5:16-25).
What does the metaphorical fruit of light look like in the believer’s daily life? Paul says that the fruit of light is in union with all that is good, right and true.
To be good (ἀγαθωσύνη; agathosyne) means to live in a way which benefits others (Romans 15:14; Galatians 5:22; 2 Thessalonians 1:11). To be right (δικαιοσύνη; dikaiosyne) means to do what God requires. To be true (ἀλήθεια; aletheia) refers to living in a biblical, historical and eternal reality.
Dr. John MacArthur writes, “Darkness” describes the character of the life of the unconverted as void of truth and virtue in intellectual and moral matters (cf. 1 John 1:5–7). The realm of darkness is presided over by the “power of darkness” (Luke 22:53; Col. 1:13), who rules those headed for “outer darkness” (Matt. 8:12; 2 Pet. 2:17). Tragically, sinners love the darkness (John 3:19–21). It is that very darkness from which salvation in Christ delivers sinners (John 8:12; Col. 1:13; 1 Pet. 2:9; cf. Ps. 27:1). The fruit of light speaks of that which is produced by walking in the light (cf. 1 John 1:5–7), namely moral excellence of heart, righteous behavior, and truthfulness (honesty or integrity).”
The believer’s responsibility before God and others is to discern (δοκιμάζω; dokimazo) judge and approve what behavior pleases God. This discernment comes from the Word of God (Psalm 1; 19; 119).
Soli deo Gloria!