they
Mark 8:16-18
16
And they reasoned among themselves, saying, It is because we have no bread.
17
And when Jesus knew it, he saith unto them, Why reason ye, because ye have no bread? perceive ye not yet, neither understand? have ye your heart yet hardened?
18
Having eyes, see ye not? and having ears, hear ye not? and do ye not remember?
Mark 9:10
And they kept that saying with themselves, questioning one with another what the rising from the dead should mean.
Luke 9:46
Then there arose a reasoning among them, which of them should be greatest.
It is
Matthew 15:16-18
16
And Jesus said, Are ye also yet without understanding?
17
Do not ye yet understand, that whatsoever entereth in at the mouth goeth into the belly, and is cast out into the draught?
18
But those things which proceed out of the mouth come forth from the heart; and they defile the man.
Acts 10:14
But Peter said, Not so, Lord; for I have never eaten any thing that is common or unclean.