1 Corinthians 3:2

I fed you with milk, not with meat; for ye were not yet able to bear it : nay, not even now are ye able;

John 16:12

I have yet many things to say unto you, but ye cannot bear them now.

1 Peter 2:2

as newborn babes, long for the spiritual milk which is without guile, that ye may grow thereby unto salvation;

Hebrews 5:11-14

Of whom we have many things to say, and hard of interpretation, seeing ye are become dull of hearing.

Treasury of Scripture Knowledge

Summary

I have fed you with milk, and not with meat: for hitherto ye were not able to bear it, neither yet now are ye able.

General references

Bible References

Fed

Hebrews 5:12
For when by reason of the time ye ought to be teachers, ye have need again that some one teach you the rudiments of the first principles of the oracles of God; and are become such as have need of milk, and not of solid food.
1 Peter 2:2
as newborn babes, long for the spiritual milk which is without guile, that ye may grow thereby unto salvation;

General references

Mark 7:18
And he saith unto them, Are ye so without understanding also? Perceive ye not, that whatsoever from without goeth into the man, it cannot defile him;

American Standard Version Public Domain