What "I" believe is not worth anything unless it is in agreement with what the bishop believes (and teaches).
For us some of us, maybe all, converts, the relinquishing of our autonomy in faith matters is a huge hurdle. But, it can be surmounted for the one thing needful.
I’ve learned that everything in the Nicene Creed was to counteract a heresy or dispute among the early Church. Does that make sense to you?