Matthew 13:51
"Did ye understand all these things?" They say to Him, "Yes;"
Matthew 15:16-17
And He said, "Are ye also even yet without understanding?
Matthew 16:11
How is it that ye do not perceive that I spake not to you concerning bread? but beware of the leaven of the Pharisees and Sadducees?
Mark 4:13
And He saith to them, "Know ye not this parable? And how will ye know all the parables?
Luke 9:45
But they did not understand this saying; and it was veiled from them, that they might not perceive it; and they were afraid to ask Him concerning this saying.
Acts 8:30
And Philip, having run near, heard him reading Isaiah the prophet, and said, "Do you, then, understand what you are reading?"