Monarchianism

I think it's pretty interesting how heresies often arise to combat other heresies. For example, Eutychianism arose against Nestorianism, Apollinarianism arose against Arianism, and now Monarchianism arises against gnosticism. The main goal of many of the variants of Monarchianism was to avoid the gnostic multiplicity of aeons. Thus many of them rejected the doctrine of the logos and were known also as alogoi.

Dynamic Monarchianism, despite being condemned in Rome at the end of the 2nd century, still managed stick around. The chief tenet was the simple, essential unity of God. The Son was simply a man filled with the divine power of God and therefore was in no way a divine person. Unlike the Arians, the DM's accorded absolutely no divine accolades to Christ. Paul of Samosata, its greatest 3rd-century exponent, taught that the divine logos was nothing more than the unspoken reason of God and therefore impersonal. The power of God in Jesus, so he said, was simply a fuller version of what Moses and the Prophets experienced. This particular heresy seemed to lack vitality, as it was too much of an outright denial of Christ's divinity to really gain any currency, especially against the backdrop of Christian liturgy and hymn that already existed.

The other (and completely) unrelated Monarchianism was the Modalist heresy. Ever heard someone say the Trinity is like water, ice, and steam? Yep, that's modalism. Also known as Sabellianism, this is the heresy that just refuses to die. It lives on today in Oneness Pentecostalism, which likewise teaches that the Son and Spirit are only different manifestations of God. However, the Oneness Pentecostals possibly differ from the old modalism in teaching an inseparable union of the human Jesus with the divine essence.

And then, in an interesting twist, the orthodox response toward Modalism often tended toward subordinationism. Getting the true doctrine exactly right seems to have been a huge challenge for the early Church, especially as the heresies grew more subtle.