Who told you that??? The book of Proverbs has ALWAYS been considered Divinely inspired Holy Scripture. Every canon, Jewish or Christian, has included Proverbs along with the others as Scripture. In fact, the New Testament contains numerous direct quotations from Proverbs and even calls it "Scripture". For example:
But he gives us more grace. That is why Scripture says: God opposes the proud but shows favor to the humble. (James 4:6)
What is this James calls Scripture? Why:
Toward the scorners he is scornful, but to the humble he gives favor. (Proverbs 3:34)
The Apostle Peter also quotes this verse in I Peter 5:5
Likewise, you who are younger, be subject to the elders. Clothe yourselves, all of you, with humility toward one another, for God opposes the proud but gives grace to the humble.
The writer of the book Hebrews quotes Proverbs, too:
And have you completely forgotten this word of encouragement that addresses you as a father addresses his son? It says, My son, do not make light of the Lords discipline, and do not lose heart when he rebukes you, because the Lord disciplines the one he loves, and he chastens everyone he accepts as his son. (Hebrews 12:5,6)
My son, do not despise the Lords discipline, and do not resent his rebuke, because the Lord disciplines those he loves, as a father the son he delights in.(Proverbs 3:11-12)
Here are some additional cross references in the New Testament to verses from Proverbs:
Romans 2:6 - Proverbs 24:12
I Peter 4:18 - Proverbs 11:31
Romans 12:20 - Proverbs 25:21-22
II Peter 2:22 - Proverbs 26:11
Boatbums, maybe we’d better first get the list of the other books that are “in the Bible” but aren’t “Scripture”
Excellent response.
It's best to use the word "Scripture" the way most people use it, I think, beause it avoids almost inevitable misunderstanding, like, "Well, this is how I define Scripture."
The Psalms and Proverbs are, as you point out, most definitely a part of Scripture for all Christians and Jews that I'm aware of.