Before conversion, the sinner is compared . . .
to a stone for his hardness of heart (Zechariah 7:12),
to a wolf for his savageness (Matthew 7:15)
to a lion for his fierceness (Isaiah 11:6),
to a bee for his sting (Psalm 118:12),
to an adder for his poison (Psalm 140:3).
"And that is what some of you were! But you were washed, you were sanctified, you were justified in the name of the Lord Jesus Christ!" 1 Corinthians 6:11
A hard heart is the anvil on which the hammer of God's justice will be striking to all eternity!