The prosperity religions define prosperous words as words that “Claim!” and “Declare” and “Prophesy!” various expression of common greed. Although the Creator God can speak and through His Word alone make it come to pass, mankind falls into the Created category of existence. The wise know that we are too use prosperous words too, but in a very different sense to how God does. We are not called, leave alone able, to bring about success in this life through our words; instead, we are called, and the wise understand this, to craft our words so that they successfully convey the intent of our words.

The heart of the wise makes his speech judicious
and adds persuasiveness to his lips.

Proverbs 16:23

The word “judicious” in the ESV is one of the words for prosperity and success in the Old Testament. However, in the context of words, it refers to words that enter the ears of the hearer with the same emphasis and meaning as intended by the speaker. The parallel second line in the verse makes it obvious with the synonym “persuasiveness”.

Every breakdown in communication is because of a fault in the speaker, a fault in the hearer, or more realistically, a partial fault in both the speaker and the hearer. But the wise will work hard on crafting their communication so that it successfully conveys their meaning. When at first something said is received differently to what was expected, the wise will revisit their words, consider the one receiving the words, and attempt in a different way to communicate the same original intent.

This is very different to the fool. The fool cares only to speak his mind with no thought for how it was received (Pro 18:2). The fool does not carefully select his vocabulary, tone, and word order (Pro 12:18). Such speaking produces misunderstanding, hurt, and destruction.

Prosperous words are words spoken, not for the sake of speaking, but for the sake of producing understanding. Such communication is successful communication. Those indeed are prosperous words.