There are two doctrines that Jesus talks about which I see as uniting points for Christians.
Baptism (John 3:3-5)
Eucharist (John 6:51-58)
Jesus assured Nicodemus that unless a man is born of water and Spirit, he cannot enter into the kingdom of Heaven. I have heard that water here is metaphorical but I don’t buy that. If water is metaphorical, then so is the Spirit. Thus, to be a Christian means accepting the doctrine of baptismal regeneration and submitting to it.
Jesus also speaks of eating his flesh and unless we actually do this, we do not have life. I suppose someone could say life is referring to spiritual life but I think that life is actual life. Therefore, I think our Lord was referring to the doctrine of transubstantiation.
It is likely that someone will say these are my mere opinions. Or compare me to a fundamentalist. That is fine. This is what our Lord said and this is what I submit to. If you do not submit to these two simple doctrines, how can you seriously consider yourself a committed Christian? I fear that since the Orthodox and the Catholics are the only denominations that faithfully adhere to the words of our Lord, that much ecumenical dialogue in the future will be taken place between them and not Protestants. I’m a Continuing Anglican in a High Church setting. I adhere to these doctrines. They are not mine, they are Christ’s. I would not want to consider myself a Christian if I didn’t adhere to these doctrines.