Mark 6:52

For they considered not the miracle of the loaves: for their heart was hardened.
— Mark 6:52, King James Version

In other translations

World English Bible (WEB)

for they hadn't understood about the loaves, but their hearts were hardened.

American Standard Version (ASV)

for they understood not concerning the loaves, but their heart was hardened.

Young's Literal Translation (YLT)

for they understood not concerning the loaves, for their heart hath been hard.