I am not infallible, but it can be clear to anyone that the Holy Spirit

is not leading the church into truth on all Bible issues, otherwise there would not be so many disagreements among Christians on so many issues. The fact is that the Holy Spirit guided the apostles on all that Jesus taught them, but after he guided Paul to write not to go beyond what is written, then that was the end of spoken tradition, and the Holy Spirit only guided the remaining Bible writers to write the remainder of the Bible. So whenever the Bible says things like we should listen to spoken tradition, that was valid until Paul wrote not to go beyond what is written. So if some pope or another leader tells you he is guided by the Holy Spirit into all doctrine, don't believe him, nobody is infallible but Jesus. So now the Holy Spirit is not guiding us with visions or anything except the Bible. And when Christians misunderstand the Bible, God is very understanding, he knows parts are difficult to understand. So don't accuse me of saying those bishops at the council of Nicea were idiots, they were just led astray by prevailing opinion, as can happen to all of us. They were not infallible, I am not infallible, and neither are you. Denominations keep changing opinions, as new opinions become fashionable. Look for example how the Catholic church changed its opinions on various issues over the centuries. God understands all that and forgives, he is very loving. Only if a church starts violating a doctrine necessary for salvation, then God has to sadly reject that church.