Look buddy, the doctrine of God as holy trinity is as old as the New Testament—where God as Father, God as Son and God as the Holy Spirit is taught throughout.
The earliest summaries of biblical doctrine, including the Apostles Creed and the Nicene Creed clearly teach it.
EVERY Christian denomination, including, Roman Catholic, Eastern Orthodox, Coptic, Lutheran, Anglican, Reformed, Presbyterian, Baptist (all kinds), Mennonite, Methodist, Moravian, Bible, Congregationalist, Assembly of God, Evangelical Free, independent Evangelical, etc. etc., regards God as one in substance, three in persons, as an essential to their beliefs. These groups would constitute well over 99% of those who call themselves “Christian” in the world today, and in history.
You want to deny God’s nature...OK, it’s a free country. Please don’t label yourself as a Christian though, as well over 99% of us find that totally dishonest.
A bit like calling yourself a “conservative” and supporting Obama.
Romans 10:9,10 is the standard for salvation.
Judging my standing with God is a sin.
Go repent. You have a lot of it to do.
Christodelphians have issues with the Trinity. So does Church of God Abrahamic Faith.
Study to show thyself approved. :)