Heresies are systems of Christian thought declared to be wrong by the early church leaders. These systems of thought were valiant efforts to find doorways into the faith that responded to questions and experimental approaches. They are valuable insights into the Christian Faith.

As time goes by a catalogue of heresies will appear along with commentary. Here is a start. 

Marcionism   

Gnosticism

Patripassianism

Modalism

Sabellianism

.Monarchianism and it's sub-sets:
        Adoptionism - Jesus is currently divine and has been so since his adoption by the Father. Jesus is not equal to the Father.
        Modalism - Son was human part of Jesus and Father was the Christ part of Jesus. 
        Patripassianism - A form of Modalism teaching that The Father came to earth and suffered.  
        Sabellianism - Reduced the status of the persons of  the trinity to being modes of manifestations of One God.