To do wrong, to act unrighteous toward someone, to harm or injure
Adikeō (from adikos, 'unjust') means to act unjustly, to wrong someone, or to do harm. It appears 28 times in the NT across many contexts: wronging a neighbor (Acts 7:26), harming someone spiritually (Revelation 2:11 — 'not harmed by the second death'), defrauding in business (1 Corinthians 6:8), and God's righteous judgment on those who do wrong (Colossians 3:25). The word is the verb form of the broader adikia (injustice, unrighteousness) word group.
Adikeō touches the heart of biblical ethics: human relationships are governed by the principle of justice (dikaiosynē). To wrong another is to violate the image of God in them (Genesis 1:27). Paul's striking statement in 1 Corinthians 6:7 — 'Why not rather be wronged (adikeisthai)? Why not rather be cheated?' — applies the cross-shaped logic of the kingdom: absorbing injustice rather than perpetuating it. Revelation 2:11 offers the ultimate assurance: the one who overcomes will not be wronged (adikeō) by the second death — final, permanent justice belongs to God.