Contradiction with Psalm 142:2
Psalms 108:1 expresses a steadfast, confident heart; whereas Psalm 142:2 shows David pouring out his complaints before God, indicating a troubled heart.
Psalm 142:2: I poured out my complaint before him; I shewed before him my trouble.
Contradiction with Psalm 13:1-2
While Psalms 108:1 speaks of a fixed heart, Psalm 13:1-2 reflects a heart that is troubled and questioning God about His presence and timing.
Psalm 13:1-2: [To the chief Musician, A Psalm of David.] How long wilt thou forget me, O LORD? for ever? how long wilt thou hide thy face from me? [chief...: or, overseer]
Contradiction with Lamentations 3:17-18
Psalms 108:1 portrays a heart filled with worship, in contrast, Lamentations 3:17-18 describes a heart that has lost peace and happiness, feeling deprived of strength and hope.
Lamentations 3:17-18: And thou hast removed my soul far off from peace: I forgat prosperity. [prosperity: Heb. good]