1 Corinthians 3:1-3 Brothers and sisters, I could not address you as people who live by the Spirit but as people who are still worldly - mere infants in Christ. I gave you milk, not solid food, for you were not ready for it. Indeed, you are still not ready. You are still worldly. For since there is jealousy and quarreling among you, are you not worldly. Are you not acting like mere men?
What do we see here? Paul describes then as not living by the Holy Spirit. Pretty strong? If someone walked up to you as a Christian and said, "You are worldly - you are not living by the Spirit" I think that would be a pretty strong indication that this person thought you had some significant spiritual problems.
Paul calls them worldly three times and basically says they are acting like non-Christians (mere men).
The good news! He calls them brothers and sisters - meaning brothers and sisters IN Christ. And later calls them infants IN Christ. They are infants, they need to grow clearly. But they are in Christ. SAVED IN CHRIST despite being described as worldly, not following the Spirit, and being compared to nonbelievers (mere men).
Wow - Praise God! We are saved in Christ despite the fact we may not be living as we should! Our salvation is by faith in Christ ALONE!