Matthew 23:28
Even so, you also appear on the outside to be doing right in front of people, but on the inside you are full of hypocrisy and sin.
Matthew 23:5
But they do all their deeds just to be seen by people. They wear elaborate Scripture texts displayed on their clothing and enlarge [conspicuously] the fringes of their robes.
Matthew 12:34-35
You children of snakes! Since you are evil, how do you expect to speak good things? For the mouth speaks what the heart is filled with.
Matthew 15:19-20
For evil thoughts, murder, extramarital affairs, sexual immorality, stealing, perjury, slander --- [all these] come from a person's heart,
Mark 7:21-23
For from within, out of people's hearts, proceed evil thoughts, sexual immorality, stealing, murder, extramarital affairs,
Luke 16:15
And He said to them, "You are people who claim to be just in the eyes of [other] people, but God knows [what is in] your hearts. For that which is held up as most important among people [i.e., fame or fortune ?] is disgusting in the eyes of God.
Hebrews 4:12-13
For God's word is alive and active and sharper than any double-edged sword. It penetrates [deep enough] even to divide [a person's] soul [from his] spirit, and his joints [from his] bone marrow [Note: This is figurative language describing the penetrating effect of God's word into a person's spiritual, inner being] and is able to judge the thoughts and intentions of a person's heart.