Probably – the greatest false teaching of all time

God never promised “money-prosperity” as a ‘guarantee’ for “believing in Him” but plenty of Christians are led by false-teachings in that direction only to be ‘disappointed’ when “it doesn’t happen” or “happens to a few”.

Why?
It was “never” promised to “all” believers (fact). God didn’t lie; men did (simple as that).

Alternately, it is “Satan” who directly tempted Christ with “money-based-wealth-prosperity” for the ‘condition’ to “worship him”:

“Again, the devil took Him to a very high mountain and showed Him all the kingdoms of the world and their splendor. “All this I will give you,” he said, “if you will bow down and worship me.”.” (Matthew 4:8 – 9)

Remember, God “never” requested any such money-based-allegiance to Him (because He is “not” Mammon).

P/S:

I’ve “never” read an instance in the New Testament where apostle Paul or others quoting verses to “claim” money-based-prosperity (‘blessings’) as is so commonly prevalent across various denominations of Christianity today (food for thought).