Two ideas are talked about in this article, in particular, the (solidarity of the) Trinity and God's ubiquity. These two ideas are profoundly implanted in the Christian confidence framework and religion - they really structure both the premise and take-off point for the Christian religion. The point of this article is to return to the (Early Church and present) doctrine of the Congregation about the Trinity and inescapability of God because of the sins and expressions of remorse connected to this creed, and to reexamine the idea of the idea 'Trinity' connected to God's ubiquity. The verifiable strategy is utilized in the conversation of the (essential) sources and to arrive at the result.
I think you have two distinct areas of research you need to pursue to answer your two points
(1) what do you mean by the early church in terms of historical period. If you mean pre 300BCE you will need to address these issues via the surviving writings of the Early Church Fathers from Clement of Rome (c90BCE) to Tertullian and Origen (third century)
(2) Credal statements about these two issues generally fall post 325 BCE and are later developments of the church fathers
Christian scriptures are more complex as sources. The earliest writings are those of St Paul whilst the Gospels date from c64BCE through to the end of the first century BCE (John’s Gospel?). Many of the church Fathers though are familiar with Gospel sayings if Jesus and some of the writings of Paul.
you’v a number of sourc
research to undertake - Good luck
The point of departure is significant. This is a subject deserving further and deeper research.