One can associate with an organization to do witness work and then for 40 years preach baby milk to others and be so absorbed in the work that he himself is not fed. The nature of the witnessing is proper because babies should not be fed meat, but the problem is that the individual does not develop. And so the Corinthians were faithful in all utterance to others, giving all the knowledge they had, but they themselves did not progress mentally with the meat so that they could grow up from babyhood to adulthood. That was the principle here in verses 1-3. Otherwise, Paul’s earlier commendation would be a contradiction.
Paul identified the Corinthians, for the greater part, as babes. They would be babes in character development and in discerning only the basics “until Christ be formed” in them (Gal. 4:19). The goal of a follower of Christ is to copy the Master as much as possible in the imperfect life on this side of the veil. Paul wanted to speak to the Corinthian brethren on more advanced spiritual things, but he could not do so because of their condition as babes. Nevertheless, he would try to bring some benefit out of the confusion that existed in the church at Corinth.