יש מתעשר ואין כל - מתרושש והון רב
משלי יג - ז
Some pretend to be rich and have nothing but others act poor and have great wealth.
This applies to material wealth. Some people live a lavish lifestyle but are really poor. It's all a show. Others live very simply but are really very rich. Don't judge others by what the superficial eye can see.
The same applies to Torah knowledge. Some people pretend to be great scholars but don't really know much at all. Others present themselves as simple ignoramuses but are really fountains of knowledge.
[Based on the Gra]