1 Corinthians 2:12

2:12 Now we have not received the spirit of the world, but the Spirit who is from God, so that we may know the things that are freely given to us by God.

1 Corinthians 3:2

3:2 I fed you milk, ¹  not solid food, for you were not yet ready. In fact, you are still not ready,

[3:2]  ¹ sn Milk refers figuratively to basic or elementary Christian teaching. Paul’s point was that the Corinthian believers he was writing to here were not mature enough to receive more advanced teaching. This was not a problem at the time, when they were recent converts, but the problem now is that they are still not ready.