Psalm 94:6-7 They slay the widow and the stranger, and murder the fatherless. [7] Yet they say, The Lord shall not see, neither shall the God of Jacob regard it.

When Jesus came, he magnified scriptural truths. He said:
Matthew 5:21-22 Ye have heard that it was said by them of old time, Thou shalt not kill; and whosoever shall kill shall be in danger of the judgment: [22] But I say unto you, That whosoever is angry with his brother without a cause shall be in danger of the judgment: and whosoever *shall say* to his brother, Raca, shall be in danger of the council: but whosoever shall say, Thou fool, shall be in danger of hell fire.

When the psalmist says: "They *slay* the widow and the stranger, and *murder* the fatherless" this goes deeper than literal killing.

Consider this, the word of God is a sword. A sword kills. God slays the old man with his word. What of the word of the enemy? His word has the power to slay those that receive it. To speak God's word is to speak love, to speak the word of the enemy (idle words) is to speak hate.

Notice that the word of God and the word of the enemy has the power to slay. But one slays in love, one slays unto life.

Now back to the words of the psalmist: the Lord does not see or regard murder? ???? not so, he said in the verse earlier that the one who *shall say* raca to his brother is in danger of Judgment. He also said:

Matthew 12:36 But I say unto you, That every idle word that men shall speak, they shall give account thereof in the day of judgment.

Understand why scripture says: Luke 6:45 ....for of the abundance of the heart his mouth speaketh.
What we fill our heart|mind with, will come out our mouth. And we will answer for what comes out our mouth (our lives speak too). Selah!