Mark 4:33
And with a number of such stories he gave them his teaching, as they were able to take it:
John 16:12
I have still much to say to you, but you are not strong enough for it now.
Matthew 13:34-35
All these things Jesus said to the people in the form of stories; and without a story he said nothing to them:
1 Corinthians 3:1-2
And the teaching I gave you, my brothers, was such as I was able to give, not to those who have the Spirit, but to those who are still in the flesh, even to children in Christ.
Hebrews 5:11-14
Of whom we have much to say which it is hard to make clear, because you are slow of hearing.