It's a mistranslation. In the English version, the Elder notes that Janus has a huge magical power that he's hiding. He says that Janus must be using the power to get close to Lavos. Ted Woolsey, bless him, accidentally screwed up the meaning of this line. It was meant to say:
Elder: I heard from the Sages-sama that
Jyaki-sama hides an amazing magical power
that surpasses even Sara-sama.
However, he hates that power, which drives
the Queen mad and torments Sara-sama, and
together with his heart...He has shut that power away.
This means Janus was reluctant to use the magic that drove the wild and unchecked ambitions of Zeal. The retranslation is in progress, and is about 70% done.