1-corinthians 3:2

I have fed you with milk - I have instructed you in the elements of Christianity - in its simplest and easiest truths; because from the low state of your minds in religious knowledge, you were incapable of comprehending the higher truths of the Gospel: and in this state you will still continue. The apostle thus exposes to them the absurdity of their conduct in pretending to judge between preacher and preacher, while they had but a very partial acquaintance even with the first principles of Christianity.

I have fed you with milk - Paul here continues the metaphor, which is derived from the custom of feeding infants with the lightest food. Milk here evidently denotes the more simple and elementary doctrines of Christianity - the doctrines of the new birth, of repentance, faith, etc. The same figure occurs in Hebrews 5:11-14; and also in Classical writers. See Wetstein.

And not with meat - "Meat" here denotes the more sublime and mysterious doctrines of religion.

For hitherto - Formerly, when I came among you, and laid the foundations of the church.

Not able to bear it - You were not sufficiently advanced in Christian knowledge to comprehend the higher mysteries of the gospel.

Neither yet now ... - The reason why they were not then able he proceeds immediately to state.

3:2 I fed you, as babes, with milk - The first and plainest truths of the gospel. So should every preacher suit his doctrine to his hearers.