Contradiction with Proverbs 28:5
While Psalms 98:3 speaks to God's mercy and truth being known, Proverbs 28:5 suggests that the wicked do not understand judgment and justice.
Proverbs 28:5: Evil men understand not judgment: but they that seek the LORD understand all [things].
Contradiction with Isaiah 45:15
Psalms 98:3 describes God's salvation as visible to all, whereas Isaiah 45:15 speaks of God as a God that hides Himself.
Isaiah 45:15: Verily thou [art] a God that hidest thyself, O God of Israel, the Saviour.
Contradiction with John 1:10
Psalms 98:3 mentions God's salvation being made known, but John 1:10 notes that the world did not recognize Him.
John 1:10: He was in the world, and the world was made by him, and the world knew him not.
Contradiction with Romans 11:33
While Psalms 98:3 emphasizes God's revelation, Romans 11:33 speaks of His ways as unsearchable.
Romans 11:33: O the depth of the riches both of the wisdom and knowledge of God! how unsearchable [are] his judgments, and his ways past finding out!
Contradiction with 2 Corinthians 4:4
Psalms 98:3 highlights visibility of salvation, whereas 2 Corinthians 4:4 suggests that the god of this world blinds unbelievers.
2 Corinthians 4:4: In whom the god of this world hath blinded the minds of them which believe not, lest the light of the glorious gospel of Christ, who is the image of God, should shine unto them.