The Talmud (Nedarim 38A) says:
אמר ר' יוחנן אין הקב"ה משרה שכינתו אלא על גבור ועשיר וחכם ועניו וכולן ממשה
R' Yochanan said, G-d only rests his presence on one who is strong, rich, wise, and humble. We learn [these traits are a prerequisite] all from Moshe.
The Talmud proves that Moshe was wealthy because G-d told him to keep the leftover sapphire from the second tablets, which he was commanded to carve.
However, G-d had rested his presence on Moshe long before he carved the second tablets, while Moshe was still in Midyan. If so, being wealthy was not a prerequisite for Moshe (The Talmud - Sotah 13A - Tells us that Moshe did not gather wealth when the rest of the Jews did).
If that's the case, how can R' Yochanan learn from Moshe that wealth is a prerequisite?