You already know the answer.
The first line from that other thread...
“Who is a liar but he that denieth that Jesus is the Christ? He is antichrist, that denieth the Father and the Son” (1 John 2:22).
It is likely that there is a more severe spiritual penalty to pay for teaching false beliefs rather than simply holding them to yourself. But that isn’t the point of this thread, so if it really tugs at you, open a thread on it.
I can understand why you wouldn't want to talk about that.