why.

Matthew 7:3-5
Why do you look at the speck in your brother's eye, but fail to notice the beam in your own eye? . . .

Romans 2:1, 21-24
You therefore have no excuse, you who pass judgment on another. For on whatever grounds you judge the other, you are condemning yourself, because you who pass judgment do the same things. . . .

but.

2 Samuel 12:5-7
David burned with anger against the man and said to Nathan: "As surely as the LORD lives, the man who did this deserves to die! . . .

2 Samuel 20:9, 10, 20, 21
"Are you well, my brother?" Joab asked Amasa. And with his right hand Joab grabbed Amasa by the beard to kiss him. . . .

1 Kings 2:32
The LORD will bring his bloodshed back upon his own head, for without the knowledge of my father David he struck down two men more righteous and better than he when he killed with the sword Abner son of Ner, commander of Israel's army, and Amasa son of Jether, commander of Judah's army.

1 Chronicles 21:6
But Joab did not include Levi and Benjamin in the count, because the king's command was detestable to him.

Psalm 36:2
For his eyes are too full of conceit to detect or hate his own sin.

Jeremiah 17:9
The heart is deceitful above all things and beyond cure--who can understand it?

Ezekiel 18:28
Because he considered and turned from all the transgressions he had committed, he will surely live; he will not die.

John 8:7, 40-44
When they continued to question Him, He straightened up and said to them, "Let him who is without sin among you be the first to cast a stone at her." . . .

James 1:24
and after observing himself goes away and immediately forgets what he looks like.