Show me where Jesus taught that God the father was once a man like us, who dwelt on an earth?
Joseph Smith was far from the first to challenge or deny the Christian doctrine of the Trinity. Ancient heresies (primarily from the 2ndโ5th centuries) centered on the Trinity, specifically the relationship between the one God (unity/essence) and the three persons (Father, Son, and Holy Spirit). These arose as the One, Holy, Catholic and Apostolic Church clarified Trinitarian doctrine (one God in three co-equal, co-eternal, consubstantial persons) against various errors. Most early heresies intertwined Trinity issues with Christology (the nature of Christ).
Here are the primary ones, grouped by type:
Modalism (Sabellianism, Modalistic Monarchianism, Patripassianism). Condemned in the early 3rd century.
Arianism (and Semi-Arianism): Major controversy in the 4th century; led to the First Council of Nicaea (325 AD) and Nicene Creed.
Tritheism - 6th century AD. Three separate gods (or independent divine beings) rather than one God in three persons. Overemphasized distinction at the expense of unity.
Subordinationism - The Son (and/or Spirit) is subordinate in essence or being to the Father (not just in role/function). Often overlapped with Arianism.
Macedonianism (Pneumatomachianism). Denied the full divinity of the Holy Spirit (viewed as a creature or lesser being). Addressed at the First Council of Constantinople (381 AD).
Adoptionism (Dynamic Monarchianism) Jesus was a human โadoptedโ as Son at baptism or another point, not eternally divine. Denied the eternal Sonship central to the Trinity.
Lesser Trinitarian heresies
Partialism: God as three โpartsโ making up one whole (like a cloverleaf). Less common as a formal ancient heresy but often listed as a Trinitarian error.
Broader Monarchianism: Stressed Godโs unity so strongly it diminished the persons (could lean modalist or adoptionist).
Some Christological heresies (e.g., Nestorianism separating Christโs natures too extremely, or Monophysitism blending them) had Trinitarian implications but were more about incarnation. Modern groups like the Mormons revive similar heretical ideas. These heresies are the reason for and what shaped creeds Christians used today.
Debates over Godโs nature, Christโs divinity, and the relationship between Father, Son, and Spirit have existed since the earliest centuries of Christianity. Smith revived and reinterpreted certain subordinationist/plurality ideas in a 19th-century American context, but he was building on a long history of alternatives rather than originating the challenge.