Be not children in mind (mh paidia ginesqe tai presin). "Cease becoming children in your intellects," as some of them evidently were. Cf. Hebrews 5:11-14 for a like complaint of intellectual dulness for being old babies. In malice be ye babes (th kakiai nhpiazete). Be men (teleioi ginesqe). Keep on becoming adults in your minds. A noble and a needed command, pertinent today.