Contradiction with Proverbs 15:29
This verse says that the Lord hears the prayers of the righteous, whereas Psalms 5:1 implies that David, who is invoking the Lord to hear his meditation, may not be considered righteous in order to be heard.
Proverbs 15:29: The LORD [is] far from the wicked: but he heareth the prayer of the righteous.
Contradiction with Isaiah 59:2
This verse states that iniquities separate individuals from God so that He will not hear them, which contrasts with the plea in Psalms 5:1 for the Lord to hear the words of the speaker, implying that iniquity does not hinder God from listening.
Isaiah 59:2: But your iniquities have separated between you and your God, and your sins have hid [his] face from you, that he will not hear. [have hid: or, have made him hide]
Contradiction with John 9:31
This verse contends that God does not listen to sinners, which contrasts with Psalms 5:1 where the psalmist is asking God to listen to his words, suggesting that God's willingness to listen is not strictly based on the sinfulness of the one making the plea.
John 9:31: Now we know that God heareth not sinners: but if any man be a worshipper of God, and doeth his will, him he heareth.