1 Corinthians 3:1-4

"But I, brothers, could not address you as spiritual people, but as people of the flesh, as infants in Christ. I fed you with milk, not solid food, for you were not ready for it. And even now you are not yet ready, for you are still of the flesh. For while there is jealousy and strife among you, are you not of the flesh and behaving only in a human way? For when one says, 'I follow Paul,' and another, 'I follow Apollos,' are you not being merely human?"

Although all believers have the Spirit, some do not act like spiritual people and cannot be interacted with on a spiritual level. Though they are in Christ, they still behave as if they are in the flesh.

When Paul was teaching the Corinthian believers, he could not deal with weighty, spiritual matters. Instead, he was restricted to the most basic of spiritual concepts, almost dealing with them as if they were not Christians. After teaching and giving them opportunities to grow, they had failed to develop as they ought to have developed. They lacked the spiritual discernment that comes from God through His word. They still saw things through an earthly, sinful, human perspective.

How was this deficiency displayed in their lives? Was it seen though moral failures like adultery or idolatry? Those problems did exist in the church, but that is not here identified as the problem. The reason for their inchoate spiritual state was "jealousy and strife." They were identifying themselves with personalities and creating divisions over them. This is human behavior and does not reflect any spirituality.

I might be prone to think, I am following this very spiritual person. He is better than these other Christian leaders. Therefore, I am spiritual, and they are not. I probably wouldn't think these words exactly, but I might identify myself with someone and follow him to the unnecessary separation of others. If a person does such a thing, he would probably think himself spiritual for it. But really, there is nothing spiritual about those kind of actions. That person is "behaving only in a human way." Truly spiritual people follow Christ and love His word.