The Zohar in this week's Torah portion (Terumah) discusses how the lower realms are jealous of the spiritual lights received by the upper realms. The Creator responds to the lower realms' lack with compassion and grants them more lights than they would have otherwise received.
The Zohar explains that this cosmic jealousy is the spiritual root of the Talmudic adage, which is usually translated as, "Competition among Torah scholars increases wisdom." The Zohar, however, reads this phrase a bit more literally as, "Jealousy among Torah scholars increases wisdom." The meaning is that somehow there's an increase in wisdom when Torah scholars are jealous of each others' spiritual attainments.
The Zohar explains that the "increase" happens because the jealousy evokes divine compassion, which moves the Creator to grant the scholars new gifts of wisdom. These new gifts mirror the new gifts of lights granted to the lower realms in compensation for their jealousy.
This passage in the Zohar teaches us that it pays to be jealous over another's spiritual attainments for a couple of reasons. Firstly, jealousy can encourage us about our own potentials, pushing us to grow even further. Secondly, like a silent prayer, the Creator's compassion can be stirred to help our spiritual growth along the way.