1 Corinthians 3:3

For ye are yet carnal

(ετ γαρ σαρκικο εστε). Σαρκικος, unlike σαρκινος, like ικος formations, means adapted to, fitted for the flesh (σαρξ), one who lives according to the flesh (κατα σαρκα). Paul by ψυχικος describes the unregenerate man, by πνευματικος the regenerate man. Both classes are σαρκινο made in flesh, and both may be σαρκικο though the πνευματικο should not be. The πνευματικο who continue to be σαρκινο are still babes (νηπιο), not adults (τελειο), while those who are still σαρκικο (carnal) have given way to the flesh as if they were still ψυχικο (unregenerate). It is a bold and cutting figure, not without sarcasm, but necessary to reveal the Corinthians to themselves.Jealousy and strife

(ζηλος κα ερις). Zeal (ζηλος from ζεω, to boil) is not necessarily evil, but good if under control. It may be not according to knowledge (Romans 10:2) and easily becomes jealousy (same root through the French jaloux) as zeal. Ardour may be like the jealousy of God (2 Corinthians 11:2) or the envy of men (Acts 5:17). Ερις is an old word, but used only by Paul in N.T. (see on 1 Corinthians 1:11). Wrangling follows jealousy. These two voices of the spirit are to Paul proof that the Corinthians are still σαρκικο and walking according to men, not according to the Spirit of Christ.