Once Jacob determined that Immortal Nimrod was probably using Soulmancy, or at least an aspect of it, within his avatar, he thought of ways to counter it.
Moreover, Jacob didn't give away any clue that he was a Soulmancer as well, while suppressing the Divine Soulless Codex in his nexus point without letting even a sliver of its trace out.
Because if Immortal Nimrod was an enemy of the Soulmancers, and the enigmatic God of Evil Void who had eradicated the entire legacy of Soulmancers, then revealing this fact would only bring Jacob harm, and he might even lose an important trump card.
After all, if the Soulmancers were eradicated by the God of Evil Void, then there was a good reason that it was done because of fear instead of rage or resentment, and there was a high chance that the God of Evil Void was also a Soulmancer.
