Contradiction with 2 Kings 20:1
This verse states that Hezekiah was going to die and not recover, whereas Isaiah 38:7 is part of the assurance of his recovery.
2 Kings 20:1: In those days was Hezekiah sick unto death. And the prophet Isaiah the son of Amoz came to him, and said unto him, Thus saith the LORD, Set thine house in order; for thou shalt die, and not live. [Set...: Heb. Give charge concerning thine house]
Contradiction with 2 Timothy 3:16
Suggests all scripture is inspired and non-contradictory, whereas Isaiah 38:7 implies the need for a sign, which could imply doubt.
2 Timothy 3:16: All scripture [is] given by inspiration of God, and [is] profitable for doctrine, for reproof, for correction, for instruction in righteousness:
Contradiction with Matthew 16:4
Mentions that an evil and adulterous generation seeks after a sign, which contradicts the concept of seeking confirmation in Isaiah 38:7.
Matthew 16:4: A wicked and adulterous generation seeketh after a sign; and there shall no sign be given unto it, but the sign of the prophet Jonas. And he left them, and departed.
Contradiction with John 20:29
Emphasizes belief without seeing signs, contrasting with the reliance on a sign in Isaiah 38:7.
John 20:29: Jesus saith unto him, Thomas, because thou hast seen me, thou hast believed: blessed [are] they that have not seen, and [yet] have believed.
Contradiction with Deuteronomy 6:16
Instructs not to test God, whereas Isaiah 38:7 entails seeking a miraculous sign as confirmation.
Deuteronomy 6:16: Ye shall not tempt the LORD your God, as ye tempted [him] in Massah.