Try to answer these, or instigate your own...
When a prophet speaks in the name of the Lord, if the thing does not come about or come true, that is the thing which the Lord has not spoken. The prophet has spoken it presumptuously; you shall not be afraid of him [Deuteronomy 18:22].
So how is Jonah not disqualified as a prophet? The Lord did not destroy Nineveh, as Jonah had spoken in His name. Indeed, does this put a different perspective on Jonah's anger when he did not see the city destroyed?-- that the Lord set him up to be a false prophet? I had thought that Jonah [naturally] hated Nineveh and wanted it to be destroyed.
Whoever speaks a word against the Son of Man, it shall be forgiven him; but whoever speaks against the Holy Spirit, it shall not be forgiven him, either in this age or in the age to come [Matthew 12:32].
A voice came to him, “Get up, Peter, kill and eat!” But Peter said, “By no means, Lord, for I have never eaten anything unholy and unclean" [Acts 10:13-14].
It is clearly indicated it is the Holy Spirit who is talking to Peter here, and slightly later, v. 9 says so plainly. So if Peter was commanded to do something by the Spirit and he said "By no means, Lord..." how did he not speak against the Holy Spirit, and thus can never be forgiven?